One thing I would suggest is that you insure the OS as you have it now is working properly. I'd insure that you have been keeping up with all the updates to this point and that your system has no errors in the registry. I did the SP3 urgrade for my system and it had no adverse affects. I do keep it up to date and it has been working fine. AS I understand it, the SP3 has some upgrades to the genuine authenication stuff and some newer security patches that weren't included in any of the updates but required the upgrade to become effective. Read the info provided by MS to be sure.