Okay, my Outlook has been functioning fine, no problems until this morning. I haven't changed any configuration in the email accounts, or anything like that. I run Outlook 2010 in Windows 7 64bit.
Starting this morning, when I try to send an email TO ANYBODY, I get a bounceback message saying:
I'm now in a situation where I cannot send ANY email, and I can't find anything online that might help me diagnose this problem. Any help is appreciated.