I did not know the previous referral was for a sales pitch. Here is another site I found that has a free on line scan with detailed removal instructions. http://www.trendmicro.com/vinfo/virusencyclo/default5.asp?VName=TROJ_ISAPASS.A In reviewing this matter, there may be a difference between the files Isass.exe and isass.exe. I did not think file names were case sensitive, but now I'm not too sure. Good luck. Tom Mayer The Isass.exe file does show up as a process in task manager (I am updated except for SP2) and I run a hardware firewall, zone alarm, spywareblaster, spybot, adaware, and Norton Anti-virus. Online scans indicate all my ports are stealthed and that my PC is invisible to the internet. I went to the website suggested below http://www.onlinepcfix.com/virushelp/sasser.htm and it is a site wanting to sell a fix for the sasser worm for $24. Shouldn't Symantec have a free fix if its protection allowed this in? Spybot and AdAware say I have no malware (yet there is Isass.exe). I don't know what to do. Ann Fennell Hi, I'll bet if you look under the hood so to speak by using something like task manager or a third party utility for showing up processes running you might just see something in that list called "lsass.exe" which might point to the culprit. Paul. Here is some information that might help: http://www.onlinepcfix.com/virushelp/sasser.htm Tom Mayer I have been trying to help a retired fellow with his computer woes. His machine runs fine until he logs onto his ISP, then it will shut down within minutes. The error message has to do with lsass.exe, and the windows displayed conform exactly to those with a Sasser worm problem. Yet, we can find no worm! Symantec's tool to remove the worm finds none existing. A Norton's AV scan says his machine is clean. None of Microsoft's list of processes that are indicative of the worm are running on his machine. Any tips? Could this be other than a Sasser Worm? Thanks for any help. Gordon Do you want to signoff PCSOFT or just change to Digest mode - visit our web site: http://freepctech.com/pcsoft.shtml