There may be one more possibility from Norton that he hasn't tried, go to...
http://security.symantec.com/nbrt/npe.aspx
and try running this elective scan on his system, may/may not help ?
Probably wouldn't hurt if he downloaded it to his computer, then ran it with his INTERNET connection on-line.

I use Norton, and haven't had a problem with it (probably luck) but, I keep my settings so tight, that my computer squeaks when it's booted, and...

I know it's a little late for this advice, but...
I have created a separate Folder on C:, I named it "Incoming" not that it matters. EVERYTHING that I create (.doc, .xl, pictures, copies of my Farorites and Documents folder) is either saved directly to that Folder, or copied frequently to it.
Then, I happen to have an external Hard Drive, which once a month or so, just copy the complete Incoming folder over to it. One can additionally make a CD as well. I then have a working copy of ALL my files.
OK, it can be as much as 30 days old, BUT, it's better than nothing.

What's important about doing it that way is...
That the Folder is NOT in the Windows system, or Program Files where most of the Virus guys like to send their attacks to. So, if/when you do have a problem, you can just re-image or replace a Program, and you do not have to loose any of your created files or pictures.

If you need to know...
Open the "Computer" file from your desktop.
Click on C:,
Right click with your mouse, and select "new folder",
Enter a name like "BACKUPFILES', and close.

Then, move EVERYTHING that you want over to that Folder, by sub-folder if you want,
and you'll have a separate from system place, to keep your important files.

Good Luck.