I get the error about halfway during a scan on my pc.

Error during check!: Virtumonde [66 - $BD8BE15E] (TRegExpr(exec): Not Assigned Expression Property) ()


Congratulations!: No immediate threats were found. ()



--- Spybot - Search & Destroy version: 1.6.0 (build: 20080707) ---

Whether or not it means it found the trojan and can't process it, or it's some kind of simple error, I have no idea. Is it JUST a spybot bug, or need I be concerned about both a bug and an infection, in which case I also post in the malware forum?