This may be the problem with the installs.
Right now, your computer has a Volume Licensing edition of XP installed, and that installation was done with a now-blocked Volume Licensing Key (VLK). VLKs are blocked by Microsoft at the request of the original keyholder for such reasons as the key was lost, stolen, compromised, misused, or expired. Also, MS may have blocked the key if it notices a pattern of misuse or more installations of XP using that key than authorized.
As a rule, VL editions of XP should not be sold to individual consumers. Businesses, schools and gov'ts normally use VL editions for flexibility in installing many computers.
This may be why you are getting errors on trying to install some programs and you likely aren't able to install any MS updates either.
Look on the computer or in the materials that came with your computer to see if you have a Certificate of Authenticity (COA).
Look for:
1. What edition of Windows XP is it for, Home, Pro, Media Center, or some other edition or version of Windows?
2. Does it read "OEM Software" or "OEM Product" in black lettering?
3. Or, does it have the computer manufacturer's name in black lettering?
Not sure what to look for and more information Click here:
http://www.microsoft.com/resources/howtotell/en/coa.mspxIf you have been sold this copy of XP as new then go here:
http://www.microsoft.com/resources/howtotell/reports/report.aspx?displaylang=enYou can call 1-866-PCSAFETY (1-866-727-2338). This phone number is for virus and other security-related support. It is available 24 hours a day for the U.S. and Canada. They will help you get your Windows validated.
Let me know if you need any more information and I will try to help. At this point there isn't much I can do.