SMS Delivery Issue to AT&T Devices

[Chad Hall]

Anyone else having issues sending notifications from ServiceNow via email to AT&T SMS devices? For many years we've used the Email2SMS functionality that nearly every US provider supports to send text messages to our users via their SMS email address. For AT&T these take the form of 'phonenumber@txt.att.net' or 'phonenumber@mms.att.net'. Beginning Friday 1/18/19 this stopped working about 85% of the time. Emails sent to these same AT&T devices work fine when sent from other sources besides ServiceNow. When a ServiceNow email doesn't get delivered we get a bounce back reply from 'general@smartmessagingsuite.com' with this generic statement in the body:

"<>
@MESSAGE@=1 033 ERROR - the request is not authenticated

Email2SMS message could not be accepted as user acxiom@service-now.com cannot be authenticated. Please check your settings before trying again."

After some research it appears that smartmessagingsuite.com is an AT&T messaging service so I know its getting to AT&T. Its next to impossible to get anyone from AT&T Support who even knows that Email2SMS even exists, so nobody has been able to help me. I opened a HI ticket and while they understood the issue I'm not sure they're getting anywhere with AT&T on a solution as its now been 5 days with no resolution. ServiceNow was able to see that our messages to 'phonenumber@txt.att.net' started getting redirected to 'phonenumber@smartmessagingsuite.com' on 1/18/19 but I have no explanation from anyone why that's happening, what it truly means, or what we can do about it.

Since it only seems to affect our ServiceNow notifications I can only assume that its a ServiceNow-specific problem with AT&T. And if that assumption is correct then I suspect it may be impacting a lot of you all as well. We rely heavily on text messages for our high priority incidents so this is kind of critical for us. Please let me know if you've encountered this or if you have any ideas on how to resolve it. And before anyone suggests that we just use the Notify plugin for direct SMS messaging through Twilio, we don't own that and its not in the budget. 

Thanks! I appreciate the help!

Chad Hall

Acxiom

[Chris M3]

Curious.  We don't generate Incidents from inbound emails, so we're not seeing that problem, and weren't aware that a response was coming back.  Can you provide any details on what the emails look like so I can see how many we're getting?  I took a peek, but couldn't find anything obvious in the logs.

[Chad Hall]

When a ServiceNow email doesn't get delivered we get a bounce back reply from 'general@smartmessagingsuite.com' with a subject of 'Response' and this as the body:

"<>
@MESSAGE@=1 033 ERROR - the request is not authenticated

Email2SMS message could not be accepted as user acxiom@service-now.com cannot be authenticated. Please check your settings before trying again."

[michaelmonocchi]

That is exactly what we are seeing.

[Chris M3]

Interesting, we're not seeing those.  Dug a bunch more, and see no kind of response in our email logs for times when I know this occurred.

Do your messages eventually get deliverd, just delayed?  Or are they just out-right not delivered?

[michaelmonocchi]

Ours get bounced back.