Our initial attempts to send text messages via Outlook or Exchange (kicked off by a Filemaker database script) were successful; however, within a week AT&T seems to be blocked. Others seems to also have this problem. http://www.knowoutlook.com/view/154389-cant-send-text-message-to-email-protected-.html
I received the following email from our Exchange Server:
Subject: Mail Delivery System <MAILER-DAEMON@p01c12o147.
Body: This message was created automatically by mail delivery software.
A message that you have sent could not be delivered to one or more recipients. This is a permanent error. The following address(es) failed: