Ok, I had an issue with WLM before, but it was because my server information was incorrect. I fixed that and it has been working fine ever since. Just yesterday, this new issue started: I can't send emails again! The messages reads:
"The message could not be sent because the server rejected the sender's e-mail address. The sender's e-mail address was 'firstname.lastname@example.org'
Server Error: 554
Server Response: 554 5.7.1 email@example.com
: Sender address rejected. Access denied
Windows Live Mail Error ID: 0x800CCC78
Someone help please! Thank you.