IM wont sign in and registration gets "Security Error"

I recently installed W7 pro from MSDN on my newly built computer and I'm having a few internet related issues.

Both issues persisted after I disabled the windows firewall and Microsoft Security Essentials to see if that was the problem.

My Pidgin and MSN messengers refuse to sign in. Pidgin gives me "unable to validate certificate" error and MSN gives me its generic can't sign in message.

When I tried to activate my product key for W7 online, it gave me a "security error" I forgot the exact error string because I have since successfully activated by phone.

How do I fix this? I have a feeling this same issue will also prevent some much needed windows updates...