It is not possible to uninstall software in Safe Mode if the service is not running, that is highly problematic if a software is responsible for PC issues.

There is however an option to start the Windows Installer Service in Safe Mode, so that software can be uninstalled afterwards.

windows installer service error

The Windows Installer Service can’t be started immediately, it is necessary to patch the Registry first.

Open the Windows Registry Editor with the keyboard combination Windows-R, type regedit and hit enter. It can also be launched by clicking on the start orb, and entering regedit in the run box in the Start Menu followed by enter.

Locate the following Registry key

HKLM\SYSTEM\CurrentControlSet\Control\SafeBoot\Minimal\

Right-click on Minimal and select New > Key. Name the key MSIService and change the default value to Service by double-clicking it.

windows safe mode

This makes the Windows Installer Service available in minimal Safe Mode. You may want to repeat the steps for the networking Safe Mode as well. All steps are the same, except for the starting Registry key.

HKLM\SYSTEM#92;CurrentControlSet\Control\SafeBoot\Network\

The Windows Installer Service needs to be started afterwards, this can be done by clicking on the start orb again, entering services.msc and hitting enter.

Locate Windows Installer in the services listing, right-click it and select start. Alternatively execute the following command via the command line:

net start msiserver

It is furthermore possible to issue all commands via the command line. To enable Windows Installer in minimal Safe Mode execute the following command:

REG ADD "HKLM\SYSTEM\CurrentControlSet\Control\SafeBoot\Minimal\MSIServer" /VE /T REG_SZ /F /D "Service"


For Safe Mode with network:

REG ADD "HKLM\SYSTEM\CurrentControlSet\Control\SafeBoot\Network\MSIServer" /VE /T REG_SZ /F /D "Service"


The freeware SafeMSI offers to automate the Registry editing and service starting. Just double-click the program in Safe Mode to enable Windows Installer.

The Windows Installer CleanUp Utility has been developed by Microsoft as a tool to clean a computer system after a failed installation of a software program using the Windows installer. The computer program will display a list of all applications that have been installed using Windows Installer giving the user the option to remove their installers properly from the computer system.

It is possible to select one or multiple programs from the list for removal. The cleanup program will then remove the installation files from the computer system so that it can be removed or installed properly. Microsoft advises to not use the program to cleanup Office 2007 installers this way. The reason for this is that it can happen that installers can become corrupted so that it becomes impossible to remove the program from the operating system.

The Windows Installer CleanUp Utility is compatible (via 4 Sysops) with 32-bit and 64-bit editions of the Windows operating system.

Users who double-click on the msi file directly will also install the application but with the possibility that it will not run properly on the computer system. Take a computer program that requires the Microsoft .net Framework 3.5 for example. If the user has an older version of the framework installed setup.exe will download the files needed and launch the installation of the compatible framework and launch the installation using the msi file afterwards.

If the user installs using the msi file the installation will go through without problems but might experience an application crash or warning message while starting the application. It is therefor recommend on end user systems to always install applications using the setup.exe file if both a setup.exe and xyz.msi are available after unpacking the software program.

There are even some msi setup files out there that will not perform the installation upon execution but request an installation using the setup.exe file instead to ensure that all necessary components are installed.