Uninstall Programs Packaged with Windows Installer in Safe Mode

Whenever you install a software in Windows, most of the time it will come with an uninstaller that allows you to safely remove the program from your computer. If you’ve installed a software and suddenly Windows has stopped working, the logical way is to boot Windows in Safe Mode and then try to uninstall. Safe mode is a troubleshooting option for Windows that starts your computer in a limited state. Only the basic files and drivers necessary to run Windows are started. Unfortunately by default you can’t uninstall a software that is packaged with Windows Installer in Safe Mode. If you try to uninstall, you will get the error
“The Windows Installer service is not accessible in Safe Mode. Please try again when your computer is not in Safe Mode or you can use System Restore to return your machine to a previous good state.”

There is a Windows Installer (msiserver) service in Services and if you attempt to manually start it in Safe Mode, you should get an error that says 

“Windows could not start the Windows Installer service on Local Computer. Error 1084: This service cannot be started in Safe Mode.”

To start the Windows Installer service in Safe Mode so that you can uninstall programs, all you need to do is add a new MSIServer registry key. Simply follow the step-by-step instructions below:

1. Hit Win+R, type regedit and click OK.

2. Navigate to the following location in registry editor:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SafeBoot\Minimal\

3. Right click at Minimal and select New > Key and name it as MSIServer

4. The (Default) data for MSIServer should show (value not set). Double click on (Default) and type Service in the value data. Close the Registry Editor.

5. Again hit Win+R, type services.msc and click OK.

6. Look for Windows Installer on the list, double click on it and click Start.

You can now uninstall programs that is packed using Windows Installer in Safe Mode. 

Alternatively, you can also do all the steps above by typing two command lines below in command prompt or at the Run window.

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

net start msiserver