I work in the IT department at a small business. We've been having some issues where an external caller calls in and immediately gets the message "Please enter your mailbox number". It's a handful of our clients who get this message, and we've been having trouble fixing the problem.

We’ve done some extensive troubleshooting with our VOIP provider and here’s what we’ve discovered:

Using a test caller in Texas, the caller was getting the “Please enter your mailbox number” prompt. The provider's switch in Texas and the router here at our location were showing the caller ID as “5077” (the last 4 digits of the 10-digit number) and then handing it off to the Mitel 3300. In the Maintenance Logs of the Mitel 3300, I’m able to see this number as “5077” but the Mitel 3300 acts as if it doesn’t know what to do with his call.

I then had our test caller in Texas dial my personal cell phone to see what I received as caller ID, and I also received “5077” instead of a 10-digit number. It appears something being transmitted from the origination point of the call is only transmitting these 4 digits.

To confirm that the problem was in how the Mitel box was interpreting this information as the culprit, the service provider shut Caller ID completely off the system, and our test caller was able to get right into the auto attendant and reach my extension.

Is there a setting in the Mitel 3300 that can be changed to make it recognize other number combinations? It seems as though if it’s not a 10 digit number being transmitted via Caller ID, then the box has no idea what to do with it.

Any help would be appreciated as I am at a loss as to where to go with this next.