There are a number of things you can do to fix this problem. Don't rush to reinstall just yet
Have you checked to see if the Windows Installer service has been disabled? You can check in one of two ways, depending on your preference.
1. Start > Search Box >
Services.msc . Look for the service titled
Windows Installer and make sure that it has not been disabled. You might also want to check and see the security context that it is running under. you would do this by clicking on the
LogOn tab and making sure that
Local System radio button is checked.
2. The other way is to open a command line window and type:
SC Query MSIServer . If you get any kind of error back, then there might be a problem with the service.
3. You can also unregister and re-register the windows installer service:
Open a CMD Prompt/ Or the start Box, and type
msiexec /unreg. Wait about ten seconds and then type
msiexec /regserver. Now trying installing or uninstalling your application again.
Make sure to empty all your temp files (system and IE) as well.
and you can also try running SFC/ScanNow