Rfc2822
The answer is really quite simple. All you need to do is check that you’ve typed the email addresses correctly in the mail that you have tried to send. For some reason if you mistype a single email address in the TO: or CC: lines of Windows Mail, the program gets it’s undies in such a bunch that it can neither send the other emails nor communicate the problem to you in plain English. It just offers you a cryptic message about RFC2822.
Here’s what to do: First ignore all of the otherwise misleading advice in this thread. Then, open the “Outbox” folder in your mail program. You’ll see all of the mail there that you’ve been trying in vein to send over the past few days. Open the very first one and verify that all of the email addresses that you’ve typed are correct. Fix or remove the offending address and you’re off to the races. If that doesn’t work, you may have to delete the problematic email altogether. Presuming the subsequent emails are ok, they’ll be sent out in turn once the problem email is fixed.
I hope this helps; it worked for me. Good Luck…
---Will