Enable Windows Installer service in Safe Mode

Enable Windows Installer in Safe Mode
1.  Click on start>> run and type in cmd then click on ok (In Vista and Windows 7 click on start and type in cmd in the search window. Right click the cmd box on top of search window and select “run as administrator”)
2.  Type in the following in cmd window.
      REG ADD "HKLM\SYSTEM\CurrentControlSet\Control\SafeBoot\Minimal\MSIServer" /VE /T REG_SZ /F /D "Service"
     
3.  Hit Enter key
4.  Now, type the following command in Run box 
     net start msiserver
5: Hit Enter key.
This will start the Windows Installer Service in safe mode.
Enable Windows Installer in Safe Mode with Networking
1.  Click on start>> run and type in cmd then click on ok (In Vista and Windows 7 click on start and type in cmd in the search window. Right click the cmd box on top of search window and select “run as administrator”)
2.  Type in the following in cmd window.
      REG ADD "HKLM\SYSTEM\CurrentControlSet\Control\SafeBoot\Network\MSIServer" /VE /T REG_SZ /F /D "Service"
    
3.  Hit Enter key
4.  Now, type the following command in Run box 
      net start msiserver
5: Hit Enter key.
This will start the Windows Installer Service in Safe Mode with Networking.