Hi, I have Norton anti virus and it alerted me to some viruses that it quarantined, however then my pc froze and when I rebooted microsoft came up and said explorer was being shut down for prevention, so basically my pc would n't run. Explorer not ie. I have rebooted in safe mode and am running norton. A few questions, how can my pc get infected when it has an anti virus software running? How has it got infected? Also I see some files created today in C: WINDOWS system32 have been deleted. It says svchost.exe was modified just after the virus came in. What can I do about this as I understand it is an important part of XP, will it be ok if all the other files are deleted?
svchost is essential to windows and must not be disabled,though you should not be able to.
There are several instances on a general pc of svchost that perform various tasks such as controlling the execution of windows DLL'S and windows services.
Problem you may have is that some viruses disguise themselves as svchost but normally changing a letter into upper case or even changing the letters CV of svchost into bold in an attempt to fool you its legit.
How you got infected maybe one of many ways,received a file,install a file etc.
Personally my opinion is that Norton is not as good as it use to be.
I would as follows:
Disable system restore (you will lose all restore points)
Scan in safemode (tapping F8 on startup)
Once happy the virus is removed,i would consider removing Norton using the removal tool click here