Incomplete voicemail configuration. The phone number of Exchange UM Auto Attendant or the Subscriber Access Number for users ...

Incomplete voicemail configuration.

The phone number of Exchange UM Auto Attendant or the Subscriber Access Number for users in this site is not configured.
Cause: Even though PSTN re-routing is enabled, the phone number of the AA and/or SA is not configured.
Resolution:
Configure the Auto Attendant and Subscriber Access phone numbers.