Within the last couple of weeks, I have noticed that when I send a message to At&t text service, I get a reply that says unable to send for the past 4 hours, will keep trying until message is 5 days old.  I can send them thru Hotmail and they go right thru.  I can also send them thru the centuryel portal page and they go right thru.  This only appears to be with At&t going thru windows live mail on my CenturyTel account.  Other cellular texting messages appear to work just fine, example Verizon.  Here is an example of a return mail.

Note: I have moved the full message header of the email you have received in the private message area for security reasons.

 Any Suggestions?

Thanks Bob