It's important to keep in mind that Status Reports are provided directly from the Carriers and can have a variety of different meanings.

If the destination Mobile Number (MDN) for the message is invalid, it can be due to any of the following:

  • The MDN is not a valid subscriber on the carrier.
  • The MDN cannot accept SMS messages.
  • A pre-paid user account has run out of funds. (TEMPORARY)
  • The MDN account is suspended. (TEMPORARY)
  • The Subscriber is on a blocked list.
  • They have message blocking enabled. (COULD BE TEMPORARY)



To quickly check if the issue is a due to a carrier switch, perform a carrier look-up. 


The steps for a carrier lookup are as follows: 


Step 1. 


Click Contacts > then click View Contacts.


Step 2. 


Search for the Mobile Number and click the details icon.


Step 3. 


Located and click the GET UPDSATED CARRIER button underneath the mobile number.




If the carrier changes then this was the most likely cause of the invalid destination message.


However, it the carrier does not change, then the contact will need to address the issue with their service provider.