Greetings,
I am having a similar issue and have read whats here so far. However:
Mitel 3300 - Using Mitel MCD 4.1
I am trying to create a non associated voicemail box extension (meaning it is a phantom extension, only voicemail, no phone associated with the extension)
We do have the licensing available.
I have used the LOCATE function to make sure the extensions I want are available.
It should be a non-prime extension - I did your check on another number that is setup how am I "trying" to set this new one up.
When I try to add them into the Telephone Directory, I get an error that says, "Telephone number is unknown"
However, it will let me create a new voicemail user, using this extension, but does not work as its not in the directory or call routing...etc.
Any help is much appreciated, thanks!