If you have a full winxp cd, run the System File checker - see win help for howIf Security Essentials is running and updated there is no need to install PC GuardYou could also try this free tool http://www.malwarebytes.org/ which will detect most malware (different from a virus)If winupdate fails, MS provides free email support for critical updates

Using any Microsoft products to scan your system for malicious software is like bringing a knife to a gun fight.Microsoft is not in the malicious software prevention, detection or removal business - it is not their bailiwick and that is not what they do. Please expand your malicious software regimen/horizons to include some more comprehensive and effective tools from folks where that is all they do.I recommend you use these tools to get your system to some known condition, then troubleshoot any remaining issues: Perform some scans for malicious software, then fix any remaining issues:Download, install, update and do a full scan with these free malware detection programs:Malwarebytes (MBAM): http://malwarebytes.org/SUPERAntiSpyware: (SAS): http://www.superantispyware.com/They can be uninstalled later if desired.When the scans run clean, then troubleshoot any remaining problems. Do you really think suggestions that begin with the words try , might or maybe are going to be helpful?I need YOUR votes and points for helpful replies and Propose as Answers. I am saving up for a pony!