Please help if you can
This is an XP SP2 system of Windows Media verson XP.
I accidentally ran a program with a trojan in it and Norton 360 put up a warning that something had stopped it from working.. Then, IE, Netscape and Opera could not access Internet sites. Firefox was working, but now, it too has failed in an endless loop doing a program upgrade that fails and tries again, with no opportunity for exit. Can't uninstall to reinestall Norton 360, which stopped functioning. Can't reinstall firefox. After reinstalling IE or Opera, still no connectivity though I can ping yahoo from cmd. All other computers on the network browse with no problems. Now DVD stopped working. Eudora was crashing on startup when this happened, but I managed to install Spyware Doctor and after running it was able to reinstall Eudora and get email again, but neither it nor hijack this find anything. I ran a full scan with spyware Doctor and it found nothing. I can't uninstall Norton. I can see all of the network drives, but can't browse. I can't even browse the web server on my gateway. Now my DVD drive just stopped being seen. When I boot I get the error "ehRec.exe Ppplication error....memory could not be read. This happened when I accidentally ran a program I downloaded from an unknown source via emule.
Can anyone shed some light on this?