It's very strange. I can send email through my personal accounts at work, but not at home -- unless I connect to someone else's wireless, then I can send email just fine. Receiving email and webmail are completely unaffected. Tried it with multiple accounts on multiple computers, it doesn't matter, they all won't send. This is the error I get: I'm using Comcast cable. Yes, I know, I know, but the only other option is Verizon FiOS and I really don't want to hand all my data traffic to a single company.