Recently I had ran a virus scan on my computer with a free-ware virus program (AVG) because I was conciously aware that Norton and Symantec programs would not run on my computer due to a Trojan virus. After scanning and removing four different trojans from my system, I began receiving a warning that said I did not have the appropriate administrative rights to open any programs. After re-scanning, eight more trojans were removed, and now I receive a warning that says “Windows cannot find [Program path name and .exe] Make sure you typed the name correctly and try again.” I also receive a warning that rundll.exe is missing when I try to access anything. I can’t run any MMC programs (Disk cleanup, defrag, etc.) or any control panel programs. What should I do to repair this problem? (PS, My windows XP key is missing, re-installing probably isn’t much of an option. If it was, how would I do it without being able to use executable programs?)