I have managed to clean one 8.1 system having found the possible miscreant in an unexpected area
This fix will generate a log for those areas
CAUTION : This fix is only valid for this specific machine, using it on another may break your computer
Open notepad and copy/paste the text in the quotebox below into it:
CMD: DEL %TEMP%\*.* /F /S /Q
CMD: RD /S /Q %TEMP%
Folder: c:\Documents and Settings\Edo\Local Settings\Temp
Folder: c:\WINDOWS\Prefetch
REBOOT:
Save this as fixlist.txt, in the same location as FRST.exe
Run FRST and press Fix
On completion a log will be generated please post that