ReadyNas Duo and Windows 7 Problem

I should have asked what "Anti-Malware Suite" you were running. Both McAfee and Norton have bad reputations for taking over PC's and not allowing some connections. I used AVG previously and have had no problems with it, although my machines currently have Avast!. I also have SuperAntiSpyware for spyware protection (Pro version) and periodically run Malwarebytes Anti-Malware as well. (You can only have one active Anti-Spyware at a time or they will conflict).