Can't remove Adware.Gen

We have Windows XP on a dell laptop and use Norton Anti-Virus. Have followed all the steps mentioned in the 8-26-09 post...safemode scan, deleting temp files, etc.  to manually remove this, but it is still showing in documents and settings. local settings\temp\ppc1A.tmp and one additional area that says unknown. We recently defragged the hard drive and it compressed after finishing?? When I try to search for the infected file, the response is that it can't be found, yet when a scan is done, we are still getting the adware.gen problem. Is there anything else I can do to get this removed? Thanks in advance for any help.