So I have encountered an issue I haven't seen before. We have a mitel 250 setup to support teleworkers phones as well as on site phones. All the on-site phones are up and going. The TW phones will boot but get stuck on the applications loading screen. The user can still make and receive calls but none of the soft/user programmable buttons are functioning. I have tried to reset the phone and the phone system, and I still get the same error. I have contacted their IT vendor to ensure the correct ports are open but am still waiting to hear back.
Any suggestions?