hello and sry for my comin german-english

i have the same problem and the trojans has antivir detected. i searched forums with people who have the same problem.
ive done all what Tech says. First disabled system restore on XP, cleaned up my temp files, then boot in safe mode and no trojans where found. then i boot up again and the trojans begin to create self again. ive downloaded the avast software and searched for viruses and trojans at bootup. no trojans where found. ive booted up normal and after 15 seconds a new trojan was found by antivir.

any suggestions what i can do now?

edit: avast even DONT detect that the .exe files are trojans. i have the newest update of avast.

exmodul32c.exe
exssd32.exe
exhdd.exe

with modified/random numbers before and after the filename