you could try several ONLINE scans &/or download a couple of more Free Scanners, update & run. You May Have to Disable BD to let them scan.
Free Download & save scanners (Be Sure to Update):
Spybot S&D 1.6: http://www.spybot.info/en/download/index.html
From your comment, BD can't get it & may have become corrupted & therefore un-reliable.
Good Luck & let us know results.
I have some sort of spyware on my PC that disables certain features. For example, every time I restart my PC my quicklaunch bar next to the Start button is disabled and I need to enable it again. My bitdefender antivirus also gets affected, some features are disabled every time I restart.