Could the Surface Go being using a different ip address than you normally use to access the forum?
There are two or three large anti-spam/anti-virus screeners used by internet service providers (they aren't anything users would normally recognize) to block some exchanges from even getting to the receiving end once an ip or email address has been flagged as a virus-base. I have a couple of customers this has happened to, and while they can receive emails from me, and while their emails will go through other isps, their accounts are blacklisted on the industrial-grade spam-blocker used by my isp. Once that happens, it can be nearly impossible to ever get the account whitelisted again -- and I've tried! (Because I like profit and so I want my customers to be able to send me orders and/or quote requests!)
It's hard to believe that those background things do any good at all, considering how much garbage still gets through, but the situation testifies to just how-unbelievably-much the internet is infested with toxic feeds. It's a tragedy when victim-accounts get taken down with the evildoers as collateral damage, but it does happen.
I can't be sure that this is the same situation, but the characteristics sound practical identical (aside from you not sending emails, only trying to access, but the same result would happen).
