I had downloaded and installed the 3CX Free edition to evaluate it with my new Cisco WIP310 and inPhonex account. After spending a few hours working through all the nuances of each piece of the puzzle, and getting the phone to make and receive calls, I decided to enter the License Key that 3CX emailed me which upgrades the Free version to the full version but limits simultaneous calls to 2. As soon as I did this, all of a sudden my WIP310 doesnt ring anymore. I can place outgoing calls with no problem but incoming calls no longer work. The funny thing is that if I click the "Free Edition" button to downgrade the software it starts working again. Kind of funny that the "Free" version seems to work better than the licensed one... Any help would be greatly appreciated.