I cannot install or uninstall any programs because I get the famous 'error code 1500 An installation is in progress'. I note that two msiexec.exe's are running in task manager. If I right click both and select End Process, they both will end, however they both reappear in about 3 seconds. I cannot use the Installer Cleanup Utility because I cannot install it. Reregistering the msi does not help. Rebooting does not help. Searching the INTERNET or this site has not yielded any solutions. I tried or reviewed most all the suggested solutions. I have no idea what is causing the msiexec to run constantly.Any ideas?1 person needs an answerI do too

In Services, set Windows Installer to manual, see if that helps. If so delete all temp files, and reboot

I tried that several times. It did not help. I even set the installer to disabled, then rebooted. As soon as I swithed it back to manual the two msi's started back up.Is there a way to find out what two processes are using the msi's?

Found this set of instructions for you: http://support.microsoft.com/kb/315353Before doing anything, backups should always be taken, especially the registry backup mentioned in the article. Also, after the unregister, you may want to flush your cache, and reboot to clear out remnant junk. Then proceed through. Good Luck Was this reply helpful? Please vote if so.