Hi trocky1,
To get rid of this error, I would suggest you to install the latest version of Windows Installer which you can download it from the link:
If you still face the same issue, try the KB article 929991.
http://support.microsoft.com/kb/929991
Let us know if it helps.
Regards,
Chethan Kumar.
Microsoft Answers Support Engineer. Visit our Microsoft Answers Feedback Forum and let us know what you think.