We recently started having an issue sending email from our Exchange server to any of the major carrier email to SMS gateways.  The email shows as being handed off to external email system (No NDR) but we never receive the SMS message from the carrier.  We've tested with other email providers and the server is working fine on the mobile carrier side.  We are running Exchange 2013 SP1 CU7.  Anyone seen any issues with this?

Hi Tracy,

I recommend you try using message tracking to analyze where these emails have gone.

More details about message tracking refer to the following article:

https://technet.microsoft.com/en-us/library/bb124375%28v=exchg.150%29.aspx?f=255&MSPPError=-2147217396

In Microsoft Exchange Server 2013, the message tracking log is a detailed record of all message activity as messages are transferred to and from the Transport service on Mailbox servers, mailboxes on Mailbox servers, and Edge Transport servers. You can use message tracking logs for message forensics, mail flow analysis, reporting, and troubleshooting.

Best regards,