Hi,
1. When do you get the error message?
2. Which application do you get the error message?
3. Have you tried contacting the publisher of the application?
Method 1:
I would suggest you to run the FIXIT or you may also try the manual steps from the link mentioned below.
How to troubleshoot problems when you install or uninstall programs on a Windows-based computer
http://support.microsoft.com/kb/2438651
Method 2:
You may also go through the steps mentioned in the link and check.
Troubleshoot installing or uninstalling programs
http://windows.microsoft.com/en-us/windows-vista/Troubleshoot-installing-or-uninstalling-programs
Hope this helps and keep us posted if you need further assistance.