The first personal computers had small disk memory. To transfer files and programs from one computer to another, they were recorded on small-capacity floppy disks. There was a catastrophic lack of memory. Memory shortages naturally prompted computer scientists to look for ways to save files efficiently. One of these methods was compression or compression of information. It turned out that in many cases the file can be made much smaller in size after conversion with a special program. Compression programs began to be called archivers. Today, using the example of one interesting story, we will talk in detail about such a useful function for every user as file compression.

The question naturally arises: why do you need to compress files now, if all the main specifications Are personal computers doubling every one and a half to two years? The RAM of a modern personal computer is from 128 to 512 megabytes, disk memory generally amounts to tens of gigabytes. It would seem that you don’t have to worry too much about file sizes.

But interest in file compression is still high. There are two main reasons for this interest. The first one, on personal computers began to reproduce and process sound and image. Sound, graphic and especially video files require orders of magnitude more memory in terms of memory space than text files. One photograph of 15x20 cm with a good resolution of 600 dots per inch or just one ten-minute musical composition exceeds the volume of Chekhov's collected works.

The second reason for interest in compression is sending files over e-mail and downloading from Internet sites audio and graphic information. Bandwidth regular Internet lines do not allow you to quickly transfer files larger than several megabytes, and therefore many servers simply do not allow large files or artificially limit the user's information transmission speed. Therefore, file compression is still relevant.

Archivers reduce some files by 5-10 times. How can you reduce the file size so much? Some files are not built optimally in terms of their size. For example, common archivers compress large files Microsoft Word five to six times, and small ones almost ten. To read such a condensed text file, it needs to be decompressed using the same program.

Many users initially had the brilliant idea of ​​trying to compress already compressed files again. The first attempt is disappointing - the compressed files are not compressed further, and with all archivers. Why is this happening?

The fact is that files are represented in computer memory as long numbers. And a number of any given length, in general, cannot be accurately represented by a number of a shorter length, even if it is shorter by only one digit. Because of this, the only way to compress data is to look for some redundant information or patterns in it. Redundant information can be removed, and patterns can be used to encode similar fragments in fewer bytes. Significant compression of audio files is possible because the average person's ear cannot distinguish part of the recorded sound, or is not annoyed by the loss of some audio information.

Once the program has processed the files appropriately, found patterns, and removed unimportant information, it will not be able to carry out this operation again. Therefore, repeated compressions do not make the file smaller. It may seem strange, but there is no redundant information in random data, for example, in recordings of radio noise at a frequency where there are no transmitting stations or in the results of a generator program random numbers. The fact is that the archiver cannot find patterns in a set of truly random numbers. It turns out that both in the condensed encyclopedia and in the results of Sportloto draws, the machine cannot find redundant information, although the encyclopedia is a concentrate of knowledge, and Sportloto draws are a long set of random numbers.

It should be emphasized that archiving programs do not analyze the content. The same information can occupy completely different amounts of memory. A page of text printed on a computer in text editor- it's only two kilobytes. If the same page is presented in the form of a black and white image with satisfactory spatial resolution, then 2 megabytes are required, that is, a thousand times larger volume. In color this page will reach 20 megabytes. If the text is read by a radio announcer, then, depending on the quality of the recording, two minutes of sound will take from one to 20 megabytes. Finally, you wanted to see the speaker reading this page: the size of the digitized file will increase by another order of magnitude.

So, the basic principle of compression is the search for patterns. There are no patterns in random data, and therefore it is theoretically absolutely impossible to compress it. Incompressibility, from the point of view of information theory, is a fundamental property of a series of random numbers. However, last spring there was a story where this statement was seriously tested. This story is all the more interesting because its main character is not a scientist, but a resourceful amateur who understands well that not only the fundamental principles are important, but also the methods of their programmatic implementation. But let's talk about everything in order.

The Internet is a very convenient medium for communication between professionals. Distant specialists from different countries can discuss problems in their field. The Usenet network hierarchy is well known on the Internet. It brings together thousands of discussion groups on a variety of topics. There is also a group there called COMP.COMPRESS. In it, experts discuss compression, i.e. information compression. Participating in group discussions requires significant preparation. Therefore, random visitors to COMP.COMPRESS do not stay long. True, from time to time one of the newcomers expresses an opinion that affects compression specialists in much the same way as the projects of a perpetual motion machine affect physicists, and the works of Fomenko affect historians. Conventionally, the problem can be called a “miracle compressor”.

As a rule, we are talking about the fact that employees of a little-known company have developed a revolutionary algorithm or even a program for repeated compression of information. It is usually stated that compression is lossless, and (most importantly) that any information is compressed many times over. Upon closer examination, it turns out that this is a bluff, but, nevertheless, this idea fix regularly appears on the pages of the computer press. A typical example. In April 1992, WEB Technologies announced the creation of a program that compresses any files larger than 64 kilobytes by 16 times. There were other companies that claimed equally amazing parameters for their programs. Some of them even managed to patent their own algorithms, however, as a result, such projects turned out to be soap bubbles.

This, of course, does not mean that data compression as a direction is no longer developing. On the contrary, almost every six months new algorithms appear or old ones are improved, compressing data more and more. Particularly noticeable is the progress in audio and video compression. If ten years ago, to record a regular film, two huge laser discs the size of a large gramophone record were required, now one CD-ROM is enough to achieve similar quality, and apparently, this is not the limit. Such successes create the illusion among non-specialists that everything can be compressed very strongly, you just need to come up with an algorithm. But we must not forget that popular audio and graphics compression algorithms compress data lossily. This means that they do not compress information so much as remove fragments from it, the removal of which does not hurt the ear or catch the eye. But even a layman, if he has the opportunity to compare, will hear the difference between really high-quality sound and compressed files.

If we talk about lossless compression, then there have been no pioneering works in it for a long time. The last fundamentally new lossless compression algorithm was invented in the 80s and is still little used due to its great complexity. In addition, as already mentioned, there is data that cannot be compressed without loss at all. This is, firstly, random information, and secondly, previously compressed information. If we assume that the compressor compresses any files without loss, then you can take a file and reduce it once, then pass it through the compressor again and reduce it again. If the operation is repeated again and again, then, in the end, the file will be compressed to one bit, saving the entire useful information, which, of course, is absurd.

Despite this, thanks to random visitors, rumors about miracle compressors regularly penetrate the COMP.COMPRESS group and irritate its old-timers. One fine day, to put an end to the issue once and for all, one of the professionals, Mike Goldman, offered all owners of the miracle compressor a monetary reward. He wrote:

Mike Goldman

I am ready to pay five thousand dollars to anyone who will fulfill following conditions. You tell me how big a file you can compress and send me $100 to prove you're serious. I generate a file and send it to you. You study it as much as you want, then compress it and send it to me along with the decompression program. I decompress the file and check to see if any information has been lost. If you haven't, and compressed file together with your decompressor is at least somewhat smaller than the original file, I will pay you 5 thousand, plus your 100 dollars.

Alexander Kostinsky

In other words, if you have a program that actually compresses any information, then you can easily make five thousand dollars. Goldman's proposal was posted on the Internet http://www.faqs.org/faqs/compression-faq/part1/section-8.html along with detailed explanations of why random information cannot be compressed and why an archiver that compresses any data is impossible. The bet went unanswered for several years, but on March 26th of last year, Goldman received an email from a man named Patrick Craig that said:

Patrick Craig

I have read your proposal. Sounds very tempting, is it still valid? If so, I would like to know the details about the decompressor - should it run on any machine or is just one platform sufficient, for example Linux?

Mike Goldman

Yes, the offer is valid. Linux is enough. Do you want to take a risk?

Patrick Craig

I'm still thinking about it. Do you only need a compressed file?

Mike Goldman

You tell me what size file you need and send me $100. I generate a file and send it to you. You send it to me compressed along with the decompressor. If the compressed file together with the decompressor is smaller than the original, I will send you 5 thousand. If you don't succeed, you can send me $100 again and try again.

Patrick Craig

Can I send compressed information not in one file, but in several parts, plus a decompressor that will restore the original?

Mike Goldman

Yes, it is quite.

Patrick Craig

I accept the challenge. How can I send you money?

Mike Goldman

Send a check or bank transfer. If you order a very large file, you must provide appropriate media. Have you already decided what size you need?

Patrick Craig

I'm still thinking about optimal size, but I believe it will be less than a gigabyte. Do you have access to an anonymous ftp server somewhere?

Alexander Kostinsky

Next comes a discussion of small details, from which it turns out that the owner of the miracle compressor is an Englishman. He now lives in Japan, where he cannot send a check to Mike in the US, so he will send the money in cash by mail. Seeing that the challenge has been accepted, Mike tries to figure out how Patrick is going to fulfill the theoretically impossible conditions, but he does not give up, answers: “wait and see” and sends the money. Note that the negotiations took place at eleven emails and passed in just a few hours. Cash travels by regular mail from Japan to the USA within four days. Mike receives the money and Patrick tells him the file size he is willing to reduce. It requires 3 megabytes. But what did Mike Goldman offer to compress for everyone?

A person risking five thousand dollars must ensure that his data is incompressible. Completely incompressible information, as already mentioned, is a set of random numbers. But it turns out that getting such a set guaranteed is not such an easy task. The program always strictly follows the algorithm and as a result of its work only pseudo-random numbers can be generated. However, there is no certainty that this series of numbers cannot be repeated or generated by such a program. True chaos can only be found in real life events.

Many experts consider radioactive radiation sources to be reliable random number generators. Radioactive substances decay in strict accordance with the theory of probability, and it is almost impossible to influence their activity under normal conditions. Cryptographers use radioactive samples to create reliable encryption keys. But there is more simple solutions. For example, the Random.org website gives visitors access to a random number generator built on a regular radio. This receiver is connected to the server via a regular audio card and is tuned to a frequency on which radio transmissions are not carried out. The source of random numbers is atmospheric radio noise. This is a very high quality generator. Special program its results can be compiled into a file, and it was from this source that Mike Goldman obtained 3 megabytes of incompressible data for Patrick Craig.

What did Patrick Craig do with them? He posted his version of events on the Internet:

Patrick Craig

Whoever offers you such a bet is probably familiar with information theory and will most likely offer data from some random number generator for compression. Theoretically, such a generator could produce anything, even meaningful text that could be compressed with a regular archiver, but there was no point in hoping for this, since Mike Goldman undoubtedly checked the file before sending it to me. According to the terms of the bet, it was enough to save just one byte, and nothing was said about saving the name of the original file. It was possible to use the file name to store several bytes of information in it, thereby reducing the overall file size by them. However, most would consider this a dishonest gimmick.

Another option is to enter the missing bytes from command line when starting the decompressor. Naturally, in this case, I had to tell Mike that he had to type in those missing bytes manually. In fact, this would mean storing information in human memory. By the way, in this way you can reduce any file to zero, and then restore it by typing byte by byte on the keyboard. However, this can hardly be called compression.

Fortunately for me, Mike allowed the use of several compressed files, and this nuance made it easy to fulfill the terms of the bet without any, in my opinion, unfair practices.

Alexander Kostinsky

That's what Patrick came up with. Let's say we have a long file of random data. We find in this file, let's say the letter "A". Now on the letter “A” we will cut the file into two parts and throw away the letter itself. We will get two files, which in total will be one byte less than the original. To restore the original, you just need to glue its two parts together, inserting the letter “A” between them.

Naturally, the source file can be cut not into two parts, but into three or more, since the letter “A” we selected appears in it many times. If we are dealing with random data, then any character will appear approximately every 255 characters. Thus, by cutting one long file in those places where it has the letter “A” and throwing it away, we turn one large file into a chain of small ones, while saving four bytes per kilobyte. All that remains is to write the simplest program, which could glue together from many chopped files one large, original one.

For Patrick, this program, which can be called a decompressor, turned out to be only 156 bytes in size. The original 3 megabyte file could be divided into approximately 3 thousand fragments, but Patrick decided to stop after the second hundred, since the algorithm was clear and the result was obvious.

On Wednesday, April 4, professional Mike Goldman received a letter from the resourceful Patrick Craig, which stated that the source file was divided into 218 parts, their total length was 217 bytes shorter than the original file. The decompressor program is 156 bytes in size, some of which was spent on storing the file name. As a result, the total size was reduced by 44 bytes. The conditions set by Mike Goldman have been met, therefore it is time to pay the promised five thousand dollars.

In the COMP.COMPRESS discussion group, to the general delight of all subscribers, who had been discussing the unexpected result for several weeks. (http://groups.google.com/groups?hl=en&ic=1&th=f2d47a8426e2de35).

Meanwhile, Mike Goldman did not pay the promised five thousand and explained his actions as follows:

Mike Goldman

By cutting the file in two and discarding one byte at the cut, Patrick actually reduced the contents of the files by one byte. But, in addition to the main content, each file also has a name, creation date, location coordinates on the physical disk, and so on. As a result, two files that are one byte shorter than the third one take up more space on the actual disk, although their apparent size actually seems smaller to us.

Alexander Kostinsky

To this Patrick Craig remarked:

Patrick Craig

If operating system one long file requires less space than two short ones, then this is her problem, not mine.

Alexander Kostinsky

Formally, he is right and, if we take the terms of the bet literally, Goldman should admit the loss, and not clarify the rules along the way. Some in the discussion group urged him to "be a man and pay the money." However, Mike limited himself to returning Patrick's $100 deposit, saying that the trick done could not be called information compression, and he regretted that the terms of the bet were not formulated clearly enough.

To Patrick Craig's credit, he did not insist on the award and admitted later that he did not at all expect to earn five thousand dollars. His main goal was to “outwit the trickster” - to show that it is possible to win against the self-confident Goldman, and on his terms, if we consider the problem as a puzzle, using a fuzzy formulation of the problem.

This story turned out to be useful for all its participants. Patrick Craig showed extraordinary resourcefulness. Mike Goldman realized how to change the terms of the bet so as not to lose it next time. And those who watched this story were once again convinced that there could be no miracle of the compressor, since the foundations of information theory and probability theory stand on a very, very solid foundation.

Good day. Today we’ll look at a fairly popular topic for beginners: working with already created sections of hard disk (you already bought a new hard drive? :) and we will consider such operations as reducing the volume (compression) of the hard drive and expanding it using unallocated area. For this we will not use any third party programs, but let’s use the built-in operating Windows system, Disk Management utility. So, why might we need this knowledge? Suppose you initially had it on your hard drive, but over time you decided that one is enough to store movies, music and photos, it’s easier to search :) Or another case, you have two local drives on your hard drive (let’s assume 2Tb), one for system (local drive C), the second for personal data (drive D), but when you partitioned them, you left too little space for drive C and this constantly creates discomfort for you. It is to solve such situations that this article was written.

In this article I will do, sequentially:
— Compression (reduction) local disk,
— Expansion (increase) of the local disk due to a new unallocated area.

This is what we need.

1) The first thing we need is to open the Disk Management utility. For the lucky owners of Windows 8.1 and 8, just right-click on the “Start” button (or in the lower left corner of the desktop for Windows 8) and select “Disk Management”. Everyone else needs to go to “Control Panel → System and Security → Administrative Tools → Computer Management → Storage Devices → Disk Management.”

3) Right-click on the partition on the right side of the window and select “Shrink Volume”.

4) A dialog box will open asking you to select the volume to compress. This window shows the current partition size, available (unused) space for compression, and the size of the local disk after compression, in megabytes. To maximize disk compression, you must defragment the partition before this operation. I'm using an empty disk, so I have almost all of its capacity available for compression. Enter the required number of megabytes in the “Size of compressed space” line and click “Compress”.

6) Now we will expand the partition using this unallocated area. To do this, right-click on the partition and select “Extend volume”.

7) The “Volume Expansion Wizard” will open, click next.

This page shows the available and selected unallocated areas, and you can also specify how much of the unallocated area should be used to expand the local disk (item “Select the size of the allocated space”). I use the entire volume, you look at your circumstances.

During my youth, it was almost the most used function - 7-20 GB disks could not contain all the necessary information. And that’s exactly what compression is for: to free up space on your hard drive. When you compress a file or folder, the data is overwritten using a special Windows algorithm and occupies fewer clusters after the operation. When you access the file in the next session, the system reverses the process before you can see even a bit of the information you need. And this, as you understand, requires time and system resources.

File compression has been a feature of Windows since the advent of Windows. disk cleanup utilities. But since the time of Windows 7, it has migrated into a separate stream: the developers felt that there were fewer problems with the lack of computer space, and compressing a huge number of files greatly slows down the functionality of Windows: when this function was activated, the system compressed all files in a row, which means that there could also be vital parameters that are accessed momentarily during the current session... Nowadays, freeing up space is easy with the help of other utilities that work in a different direction, and/or by running . In the end, any archiver program can do much more than the function described. However, she is there, let’s get to know her.

By the way

The function and approach to compression in Windows 10 has seriously changed and, it seems (for now, at least) for a much better reason. But about this in a separate article.

A couple of paragraphs of theory...

The NTFS file system uses the “ compression unit” in order to determine the degree of partitioning, granularity of the byte range stream, as well as their alignment or grouping into blocks. The size of this very unit depends only on the size of the cluster in NTFS system. Until the last moment, the following table was used to calculate the cluster size:

As you can see, starting from a certain point, exceptions begin: “native” NTFS compression stops working on volumes and partitions whose cluster size is selected to be more than 4 KB. For sizes from 8 KB compression begins to be used for sparse files. Such files are another strong point of the NTFS file system, which allows applications to create very large files, which, strange as it may sound, can exceed the size of the parent directory. This happens because the lion's share of the contents of such files (and sometimes completely) is filled with zeros or zero chains. In this case, the file system logical clusters does not provide such chains. And NTFS creates only a “pointer to where the virtual number of clusters is filled.” What does compression have to do with it? NTFS, when working to compress a file or folder, divides the data stream using the same principle. Moreover, the compression process is individual for each file; the degree of compression and subsequent operations with the file are very dependent on its actual size.

Compressing files and folders

The function is available from the context menu by right-clicking on the desired file/folder. She is here:

We activate the function, compression has begun. After this, you can force Windows to highlight compressed files. This is easy to do with a whole disk. We will find in Windows Explorer list of volumes and also call context menu right mouse:

Compress disks and files. What do you need to know?

• Compression is available ONLY for the NTFS file system
• If a file is moved from ordinary folders in compressed folder of ANOTHER DISK, it also undergoes a compression procedure
• If a file is moved from ordinary folders in compressed folder on the SAME DISK, compression is canceled and the file/folder returns to its original size
• Files compressed using NTFS compression cannot be encrypted: duplication of procedures in any form is excluded in Windows, and therefore...
• You won't be able to compress an already compressed file either)))
• Do not confuse with archiving (in zip, rar, etc.)

Compression. What not to do.

As you may have already realized, Windows compression is not a feature you should mess around with. However, understanding the compression function (at least within the paragraphs at the top of the article) can help you determine the root of the errors that appear. The most typical of them, and this may be the fault compression functions:

• There is not enough disk space. This error may occur to you precisely at the moment of copying a file/folder or at the stage of creating a backup copy.
• Error copying large files to a compressed folder
• Compressed VHD files reduce virtual machine performance

Do not compress the disk with the operating system installed on it! System disk WITH: You cannot undergo this procedure. Most often, device drivers suffer from this, refusing to start a whole set of devices that just seemed to be working. After the compression procedure is completed, the operating system will most likely not boot in the new session. But if - I don’t know what made you - you decide to do it, do not touch at least root directories.

After compression the system does not boot...

If I’m late with my advice, and you’ve already encountered a failure to start the system after compression, know that those few, but extremely important files for booting the system, were compressed. And during system startup, the “de-compression” procedure is not provided. As a result: the system does not start or Windows is constantly restarting. And you will have to work hard.

In such cases, I always use a universal option - this is an external box with a hard drive installed inside, on which a whole bunch of images of Windows boot disks of any model and bit capacity are always ready: from Windows XP to Win10 32 and 64. And I don’t worry about countless disks and flash drives.

Set the BIOS to boot from the drive with Windows disk inside:

select the language and in the installation window select System Restore:

The times of archivers are gradually coming to an end and every year, users compress information less and less often.

This is not surprising when there were hard drives designed for only a few megabytes, without even compression regular texts, it was impossible to do, but today you can buy additional memory without special expenses.

Out of habit or because of their worries about excess disk space, some still continue to compress data, but this does not always work. Why are the files not compressed by the archiver? The fact is that there is no point in trying to compress some data at all, since it is impossible.

What files are not compressed by archivers?

Let's start with the fact that data that has previously been processed through an archiver cannot be compressed. The program has completely reduced the possible memory footprint by replacing all duplicate data, so re-archiving does not help.

This method can only work if the second compression is performed using more recent software.

As for music and video files, they don’t need to be compressed at all. Video recordings are compressed by archive codecs by default, so adding them to the archive will not help reduce the amount of memory consumed.

Audio files can be added to the archive for compression, but the maximum that you can “carve out” is 5-7% of the memory; you must admit, because of this, you don’t have to waste time on archiving at all.

It is also better not to archive graphic elements (pictures), but to compress them by editing. For example, you can change the number of colors, because you don’t always need to transfer several thousand color schemes, sometimes a 256 color palette is enough.

Also, reducing the size of images and changing the format is a great space saver. Everyone knows that PNG files take up much more space than the usual Jpg format.

You can try to compress programs and various databases, but if you received them from official sources, this is unlikely to succeed. The fact is that they are optimized in advance for faster downloading.

But if archivers are not so needed today, why do their developers continue to release updates and even sell them? software products? It’s not difficult to explain; thanks to archivers, you can conveniently group data, for example, so as not to transfer them over the Internet one at a time.

Also, by archiving information, you can increase its protection, because even in the standard set

Editing partitions and volumes helps out with thoughtless disk layout at the beginning Windows installations. Any shortcomings made during installation can be easily corrected.

Why do you need to change hard drive partitions?

Because of large quantity programs and games that take up almost everything free space, Windows starts to slow down, and defragmentation of partition C is carried out with errors.

The main reason for changing partitions hard drive is the lack of space on the system partition C.

At this time, up to several hundred gigabytes are empty on partition D, but moving some files to partition D forces you to reconfigure many third-party applications. In this case, it is easier to expand drive C at the expense of D.

How to expand C drive

Expansion of drive C is possible using: Windows tools, and using third-party programs.

Extending the C drive directly in Windows 7

If you want to expand the disk using standard means Windows, then do the following:

1. By pressing the Win + R buttons, bring up the “Run” window. Enter the command "diskmgmt.msc" and click "OK". The command “diskmgmt.msc” will open the Disk Management utility
2. Select partition D and in the volume context menu click on “Delete volume”. Do not rush to edit hidden drives without a volume name, since deleting a partition will destroy all valuable files stored on it. The necessary information should be copied to another disk in advance or removable media.You cannot remove drive C, on which the system itself is installed. After disk D is destroyed, there will be unallocated space in its place.
   Select the volume and delete it
3. Select drive C and in the context menu give the command “Extend volume”.
4. Set the number of megabytes that will be added to drive C. It will not be possible to exceed the maximum value, since the physical media itself is limited. Click Next.
   The size of the previously unmarked area will decrease by this amount.
5. Drive C will be enlarged. The size of drive D will be reduced by the megabytes given to drive C. Click on a free area of ​​the drive and give the command “Create a simple volume”. When recreating volume D, this partition will be automatically formatted (quick format using Windows tools).
   Click on the remaining unallocated area and click on “Create Simple Volume” in the context menu

Now there is enough space in C for normal Windows operation and your programs.

If desired, you can use third party applications, for example, Acronis Disk Director or Partition Manager. But it should be remembered that in the hands of inexperienced users alternative programs often become not a “magic wand”, but a means of destroying user files, and only in a computer service center will you be able to recover lost data.

Video: Extending a volume using Windows 7 tools

Expanding the C drive when reinstalling Windows 7

When installing Windows, you will not skip the stage of changing disk partitions. During the reinstallation process, the program will ask which partition to install the system in and will suggest redistributing the hard drive space.

There are two types of Windows installations: upgrade and full installation. The update is carried out on top of the existing system, saves everything installed programs, but resets system parameters. Full installation - installation with formatting system partition, or installation on another hard drive partition. If you want to change hard disk partitions, then you need to choose the second installation type.

If you really need a “clean” installation of Windows, do the following:

1. Paste installation DVD or flash drive and restart the PC.
2. To open the BIOS window, press the Del, F2, or Esc key during system startup (the choice of key depends on the computer manufacturer). In the window that opens, use the arrows to select “Boot”.
   In the window that opens, use the arrows to select “Boot”
3. Next, use the arrows to open the “ Boot Device Priority" and in the list select the boot device from which you need to boot the system. Close the BIOS and save the changes.
   In the list, select the boot device from which you need to boot the system
4. Wait while the installer downloads to RAM PC.
5. Select type Windows reinstallation.
   Select full Windows 7 installation
6. For example, one disk and one partition are taken. Select the drive and click Disk Setup. All your files should be copied to other drives in advance.
   Select the drive and click "Disk Setup"
7. Additional links will appear - click the “Delete” link. A warning about data transfer will appear, click “OK” and delete the partition. Do the same with adjacent sections (D, E, etc.), if there are any.
   Click "OK" if your personal files have been copied to other media
8. After removing the existing partitions, you will have an unallocated (unformatted) disk area, which is the full size of the hard drive. To create new sections, click the “Create” link.
   Windows 7 Setup will help you create new logical drives
9. Specify the size of partition C, and create partition D in the same way. Go to partition C and format it. A quick format will be applied (clearing the disk table of contents).
   The installer requires you to format partition C

After formatting, Windows will continue to be reinstalled. Section C has been successfully modified.

Video: resizing partitions during reinstallation of Windows 7

Why can't I expand a volume in Windows 7?

A situation where the “Extend volume” option is inactive is possible. For example, we take the extension of the same C drive.

A situation where the “Extend volume” option is inactive is possible

• a spanned volume was created as D, which includes, for example, disks D and E. Transfer files from these partitions to other media. Remove this spanned volume;
• you forgot to delete all subsequent volumes, including drive D. Expansion previous volume only works when the next one is deleted.

How to delete a volume

You can only add an unallocated partition to a disk, which appears after deleting a volume.

Deleting a volume in Windows 7

To delete a volume:

You will be left with free space the size of this volume, which can now be attached to another partition.

Why can't I delete a partition or volume?

In some cases, removal may be difficult.

The reasons are as follows:

How to remove the swap file

To make volume deletion available, do the following to eliminate the Windows page file:

1. From the Start menu, go to Control Panel.
   From the Start menu, go to Control Panel
2. Go to the “System” section.
   Go to the "System" section
3. Go to "Advanced system settings".
   Click on "Advanced system settings"
4. In the "System Properties" window, go to the "Advanced" tab and click on the "Options" button in the performance settings. Click this button
5. In the performance settings window, select the “Advanced” section and click on “Change”. Select the “Advanced” section and click on “Change”
6. In the settings window virtual memory Uncheck the option to automatically select the paging file size and check the box next to “No paging file”. Click on the "Set" button. Uncheck the option to automatically select the paging file size and check the box next to “No paging file”
7. Click "Yes" when prompted to clear the page file.
   Answer yes to the request to clear the page file
8. Close all windows by clicking "OK" and restart your computer.

Go back to Disk Management and try to delete the volume again. Check if it is connected this volume with an adjacent volume in the same partition.

How to shrink a volume

The disk can also be expanded by compressing it. As a result of compression, free space will be obtained, which can be used to create a new partition or volume.

Features of volume compression in Windows 7 are as follows:

• compression works only for primary and secondary partitions, as well as in the NTFS file system. If the partition or volume is formatted in FAT32, move the data from it and reformat (or convert) it to NTFS.
• To do this, call the disk context menu and click “Format”;
• if a partition or volume has many bad sectors, it will not be possible to shrink it; The page file, hibernation files, and recovery point data present an additional challenge to compacting partitions and volumes. Beyond the second area free space

, counting from the beginning of the volume, compression will not work.

Shrinking a volume using Disk Management

If you want to shrink a volume using standard Windows tools, then:

Shrinking a volume using the command line If the option to shrink a volume in Disk Management is no longer available, use the command Windows string

1. . It can bypass the inactivity of some actions that are hidden by the Windows graphical shell. The instructions are universal for Windows 7/8.x/10. Search for the Command Prompt application in Start and run it with administrator rights. For tasks beyond the use application programs
   , Windows often requires administrator privileges.
Launch the Command Prompt application with administrator rights
2. This command displays a list of disks, partitions and volumes. The command line reports the maximum available volume space for compression Enter "shrink desired=(number in megabytes)" which you want to shrink.
   The “desired” attribute is a variable that corresponds to a value in megabytes

When volume compression is complete, the command line will display a message indicating that the volume was successfully reduced by the specified megabytes. Using the Disk Management application, make sure that there is free space in which you can create a new volume.

Video: Shrinking a volume using the command line

Expand, compress, delete, add new partitions and volumes using standard Windows utilities- it's not difficult. The main thing is not to lose valuable data that you have been collecting and creating for many years.