Windows installer error is one of the most common pop-up problems encountered by users of the Windows operating system.

The error may appear regardless of your OS version.

Reasons for the error

You can scan the OS using the Sfc /scannow command. You need to enter it into the command line window.

You can also launch the command line in two other ways:

• Start -> All Programs -> Accessories -> Command Prompt.
• Start -> Run and enter the program name cmd.exe

In a few minutes you will be provided with detailed information about OS disks, corrupted files, problems with services and other system programs.

The command line will not only find corrupted and corrupted files, but also replace them with functional ones.

After scanning, close the command prompt and restart your personal computer or laptop. Try running the installation process of any executable file.

Microsoft also offers users an automatic utility that can solve the problem with the installer.

Go to the web address of the company's official website https://support.microsoft.com/ru-ru/mats/program_install_and_uninstall

In the window that opens, click on the “Run Now” button. The utility will restore the correct configuration of the installer.

It is worth noting that the utility does not work with the eighth version of the operating system.

Configuring installer access to msi files

The installation problem may be caused by the installer not having access to msi files. The user can resolve this problem independently.

Follow the instructions below:

• Find your installation file and right-click on it;
• Select the properties window;
• Go to the security settings tab;
• In the groups or users text box, check to see if there is a user named "system". If it is not there, you need to add the user manually;

• To add a new user, click on the Edit button and then on the Add button;
• In the text field for the names of the selected object, write the word “system” (without quotes). If you are using the English version of the operating system, enter the word System;
• The entered word should instantly become underlined, as shown in the figure below;

• Check the box next to Full access and now click on the OK button;

The installer will now be able to access the executable file. The installation should complete without problems.

Please note that in some cases antivirus software may block access to the installation file.

To solve this problem, you need to log into the operating system under an administrator account, turn off the antivirus and enable compatibility with other OS versions in the antivirus properties settings, as shown in the figure below.

Windows Installer Error - Troubleshooting

Error " The Windows Installer service cannot be accessed. Windows is running in protected mode or the Windows Installer service is not installed correctly. Contact Support" may occur when trying to install any program.

The Windows Installer service allows you to add, modify, or remove applications provided by the Windows Installer (*.msi) package. An incorrectly configured service may make it impossible to install any programs.

To resolve the error, you need to perform three steps:

1. Check service availability

To do this you need to go to Control Panel — Administration - Services

Find the service in the window that appears Windows Installer (Windows Installer).

Double-click to open the Windows Installer service properties.

On the tab Are common in field Executable file should be the value: C:\WINDOWS\system32\msiexec.exe /V

On the tab Dependencies In chapter This service depends on the following components there must be Remote Procedure Call (RPC).

2. Check the launch program for the .msi extension

Open My computer or any folder. From the menu, select Tools - Folder Options and go to the tab File types.

Highlight the MSI extension and click the button Additionally. In chapter Actions There should be three actions: Restore, Delete, Install. If they don't exist, you need to create them.

Action: & Restore
"C:\WINDOWS\System32\msiexec.exe" /f "%1" %*

Action: & Delete application executing the action:
"C:\WINDOWS\System32\msiexec.exe" /x "%1" %*

Action: Install application executing the action:
"C:\WINDOWS\System32\msiexec.exe" /i "%1" %*

3. msiexec registration

On the menu Start - Run dial command msiexec/unregister and press ENTER. Then run the command there msiexec /register

After you complete all the steps above, the “Cannot access the Windows Installer service” error should disappear and all programs will install and uninstall normally.

When installing programs using msi files or randomly while the computer is running, the error “Could not access the Windows Installer service” may occur. Sometimes the failure can take the form “Error reading file XXX ....”, where XXX is the path to the msi file. The problem is that the msiexec.exe utility is malfunctioning.

First of all, to fix the problem, you need to make sure that Windows Installer is running. To do this, press the Win and R keys simultaneously and run the services.msc command. In the new window, find the line “Windows Installer” and double-click on it. Here we check that the “Startup Type” field is set to “Automatic” and the “Status” field is set to “Started”.

Solving an error with Windows Installer

If this does not lead to success, then try the following methods:

1. Re-register the installer. To do this, open a command prompt with administrator rights. If your Windows is 32-bit, then run the following commands one by one:
   • msiexec/unregister
   • msiexec /register

   For a 64-bit OS, different commands are required:

1. • %windir%\system32\msiexec.exe /unregister
   • %windir%\system32\msiexec.exe /regserver
   • %windir%\syswow64\msiexec.exe /unregister
   • %windir%\syswow64\msiexec.exe /regserver
2. Check that all OS files are intact and present. To do this, it is best to use the SFC or DISM system utilities.
3. Use a special utility from Microsoft. It is available for download from this link and is designed to automatically fix Windows Installer errors.

I have had a couple of laptops damaged by “optimizers” and filled with programs installed together with them. Inexperienced users still believe in “optimizers” and don’t look at the checkboxes when installing, but that’s not the point. After cleaning, I started updating the software and unexpectedly (for the first time in my life) encountered the following error during installation:

The Windows Installer service could not be accessed. Windows Installer may not be installed. Contact support for assistance.

The error occurred during installation from msi (for which the service itself, among other things, is responsible). Maybe the service is turned off? We go to Control Panel - Administration - Services and do not find the one we need in the list. Did the optimizers optimize? We google for a long time, read a bunch of advice that doesn’t apply, study the question along the way and come to the following:

1. Let's check whether Windows Installer actually exists on the system. Press Win+R, in the “Run” window that appears, write msiexec, click OK. If the Windows Installer Help window opens, the service is in place. But why is it not in the list of services?
2. Let’s re-register the service in the system: open the “Run” window (Win+R) and write msiexec /unregister , then “Run” again and msiexec /regserver .
3. Go to Services (Control Panel - Administrative Tools - Services), find “Windows Installer” (Windows Installer for the English version).
4. All OK. We check by installing from msi. If not, then my method did not help you, Google will help.

Some users are faced with the fact that applications are not installed and a message pops up saying that the Windows installer is not installed or is not running. How to solve this problem and install the necessary utility will be described in this article.

Checking if the service is running

One of the main reasons for such failures is stopping the installer service. To check this, you need to launch the Run utility, which can be done through Start, and then enter the services.msc command into it, which can be seen in the image.

After this, a window will open in which all services, both active and not, will be displayed. You need to find a service called " InstallerWindows" and open it. The parameters should be the same as in the picture.

In seven you can try changing the startup type to automatic; in eight this action is not available. If the user changes the startup type, the device should be rebooted after this. However, you should try to run it in both versions. Then you need to start installing the program again.

Correcting errors manually

If the previous method did not help correct the situation, then you can re-registration of the service on one's own. To do this, you will need to run the console as an administrator. This can be done through the Start menu. On the command line you will need to enter the following operators:

Such commands are required for 32-bit operating system. And these will need to be used for 64-bit Windows. After completing the work you will need to make restarting the device and try again to install the necessary utilities. The installer service should start.

Using the registry to reset parameters

It is also possible that the error lies in the registry. You can use one of the programs to recover records, but it is not a fact that they will help. It is better to open the registry editor yourself and find the following entry there:

This folder should check the ImagePath entry, the value of which should be the same as in the image. If this is not the case, then it is worth editing it.

For 64-bit operating systems, it is also worth carrying out file checkWOW64. There should be a hexadecimal number system, and the value should be 0.

After editing the registry, you should to restart a computer and check its functionality.