Problem with external network extension

Hi Everyone!

I am relatively new to PBX and inherited an already running PBX system at my job.

Things had been running smoothly until now when one of our employees, who works remotely, phone stopped working properly.

When I try to call him on his extension, it rings twice and goes to voice mail (he never hears or sees the phone ring). He also cannot dial out, when he tries to call someone its blank and eventually gives an error tone. What puzzles me is he can see what other extensions are busy with the BLF lights, so the phone is getting through to our network.

I have also tried setting up my phone and another remote employee’s phone with his extension and they work.

Does anyone have any idea what would cause this problem? I am wondering if its the phone itself, but I want to be sure before I send a new one out.

Your help is greatly appreciated!