If a virus/trojan/parasite gets past Norton, it can disable that or hide. It's also true that some pests are not detected by Norton since "it's not a virus." Here's a note about parsites, tests and removal tools.
arasite removal programs.
http://reviews.cnet.com/5208-6132-0.html?forumID=32&threadID=1313&start=0 notes the five scanning tools and removal tools that are fairly safe. If one does encounter an issue, its always been damage done by the MALWARE. The most common issue being Layered Service Provider replacement which you can use LSPFIX (Hint: use http://www.google.com to find).
The thread has follow on discussions about new links if you don't want to use Google to find an item.
Bob
PS. All the tools are free.
I logged on to my PC tonight and a message popped up:
Make sure the program V3FAXE28.EXE is running before printing. Make an icon for the program and place it in your start up group. I clicked on OK and it kept popping up. I did a system restore to 9:30 this morning and it was still there. I did a system restore to yesterday morning and it didn't appear again. Is this a legitimate program? I am running XP Pro with multiple users. I ran Norton immediatelyt and nothing showed up.

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