Had a very similar problem, same few days ago, with outlook. (I think there had been a recent Norton update by the way - not sure if it is significant). As soon as I disabled the firewall the send/receive worked without problems. In the end, shortly before reinstalling Norton, I removed all the program rules from the firewall/configuration/programs (or somesuch) window and let all the permissions/rules etc start again from scratch ie each time I ran program or connected etc I got a new pop-up saying Norton has created rules for ............. . Now it works fine.
Editted:
Ah - beaten to it by your own reply!