Ok, I think I'm on to something but I'm not sure yet why it is happening or how to fix it. The main part of the error message I get back is this:

Connected to 207.96.250.22 but connection died. Possible duplicate! (#4.4.2) I'm not going to try again; this message has been in the queue too long.

It appears that this IP is called Kerio Mail Server 6, and when I type it directly into explorer it takes me to a page asking for a username and password. I suppose that would explain why it times out after a day....the page is waiting for user input and never gets it, so it eventually dies. But I what I need to know is WHY is my message going to this server and why are only microplay.ca domain names doing this and being affected. And how do I stop it from doing this? Any thoughts?