Running windows 2000 prof client on 2000 domain, installer service always worked on this client machine. Stopped working, checked in services and the service was not started. Cannot start service. Receive an error when starting “Could not start thewindows installer service on local computer. Error 5. Access is denied.” Have tried everything can think of. Updated service pack and installer to SP3 installer 2.0 . Logged in as local admin,logged in as domain admin, the service cannot be started.Cannot install Windows installer again because installer won’t run! Catch 22. Any ideas would be appreciated. Search MS Knowledge base but can’t install my latest version of technet because of this problem.