This is something I feel needs to be addressed. When updating your operating system, adding new software the #1 Rule is this;
Unwanted stuff on your computer like viruses or spyware can cause havoc on ANY software installation, especially a major operating system upgrade like upgrading XP SP1 to XP SP2.

When people come here asking for help removing infections, trojans, hijackers, etc. the KEY thing, BEFORE ANYTHING ELSE, that must be done is get the computer CLEAN.

AFTER the computer is pronounced clean, THEN and ONLY THEN, is the time to post the advice that the operating system should be updated to the latest updates or upgrades. It should not be mentioned before then IN THE THREAD, but don't hesitate to notify the person helping the poster with removal by PM that you have noticed this in the log. We all have missed something in logs and often times it HAS been the need for the upgrade or update to the operating system.

We have had, in recent months, at least one instance, of a person doing his upgrade from XP SP 1 to XP SP2 right in the middle of the clean up procedure, and while the computer was still infected, because somebody stepped into the thread and told the poster he really should upgrade his system before going any farther. This complicated the clean up procedures and quite possibly resulted in a corrupt upgrade to SP2.

We ALWAYS welcome suggestions when working with a poster on cleaning the computer, but these should be suggestions for cleaning or comments noting something missed in a log, NOT suggestions to upgrade a program or operating system until the computer is pronounced clean.

When working on an infected computer the only updates or software installations that should be done at that time are anti-virus programs, anti-spy programs or anti-adware programs, special & approved removal or cleaning tools...ALL others can and should wait until the computer is clean AND SAFE again for updates and new programs.

On Microsoft's own page on getting ready to update to SP2 step #1 is "Check your computer for unwanted software." Unwanted software refers to malware/spyware/viruses and trojans NOT just software you have personally installed that you think you don't want anymore, unless it is actually the offending program which brought the malware with it of course.

 Also, according to Microsoft;

Spyware seems to be the number one cause of problems when upgrading to XP SP2.

For those posting for help, also some advice;

While working on the cleanup, don't download music or videos, do a lot of gaming, peer-2-peer file sharing (which can be dangerous in iteself and could have brought on your problems in the first place)...ALL of this can and most likely will complicate the cleaning of the machine and will lengthen the time it takes for cleanup.

If you think your computer is infected the first steps to take are here;
READ ME Before Posting A Request For Assistance!

When the computer is finally pronounced Clean and Safe the next steps that must be taken are here;
PROTECT YOURSELF FROM MALWARE: Tools & Tips

I say again, as I did above, we ALWAYS WELCOME help and suggestions when working a thread. WE NEED HELP, if you are not sure if your suggestion or comment is the correct one for that particular thread, by all means please feel free to PM the person working with the poster to ask if your suggestion is correct or needed, we will answer as fast as possible. I, for one, can use all the help I can get. So please feel free to be in contact with all of us.
Judy