You can visit the following link to get the release key of TC7.x:
The serial number of the unit should be under an active contract. If you only get an option of TCNC key on the web page, you might need to engage your Cisco Sales/Accounts team or open up a case with licensing team.
I'm not able to access my old voice mail messages all of a sudden. The recording says something like 'the message is currently not available'. This has never happened before in all the years I have been using this system. I have t...