Windows Installer will not work under Safe Mode, this means that programs cannot be installed or uninstalled in safe mode without giving a specific command using msiexec in command prompt.

To make Windows Installer work under safe mode, you need to create a registry entry for every type of safe mode you are logged in to.

1. Safe Mode.
   Type this in a command prompt:

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

   and then

   net start msiserver
   
   

   This will start the Windows Installer Service.

2. Safe Mode with Network
   

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

   and followed by

   net start msiserver 
   
   

   This will start the Windows Installer Service.