Failsafe MSI

Failsafe MSI (FSMSI) is a Windows shell script that enables and starts the Windows Installer service in fail safe mode. This is particularly useful for removing applications that are preventing normal system startup but still require the MSI service to be running to be properly uninstalled.


Platform Version Package Size
Windows 1.0 – 2009-04-03 fsmsi.cmd (right-click -> Save as…) 3.6 KB
Git repository Development


  • Run fsmsi.cmd with elevated privileges (Run as administrator). “Add/Remove Programs” will be opened if the script completes successfully; an error log will be shown if not.
  • Run fsmsi.cmd deactivate to reverse the changes (disable MSIServer in Fail Safe).


  • Windows 2000 or later.


Failsafe MSI (FSMSI) is released under the MIT license.