Backdoor.Tidserv has been appearing daily on my PC. Every time it is caught and quarantined by NIS. So far, so good. But my newbie question is…where’s it coming from? (NIS doesn’t know). What kind of file does it usually ride in on? Why does it keep coming back–is it something on my computer, or something in the startups I have, or ? While I’m very pleased that Norton takes care of the daily problem, I’d be happier if it was gone once and for all. Any information about this virus would be appreciated.