Limitations on Transferring Conference Calls

A client recently reported that they were no longer able to transfer conference calls to their mobile phone. I invited them to a conference to test and I was able to, however upon performing a screen share session with them I confirmed that they were not able to. Upon logging into their environment with a test account I confirmed that the test account was also unable to transfer conference calls:

We then tested and we were able to transfer a call when it was a peer to peer session. This made me think that this has to be due to a conferencing or voice policy. I checked and found that there was no difference in the configuration between my configuration and the clients. I spent some time reproducing and looking at each of the client’s .UCCAPI logs thinking it was something that was being denied in the in-band-provisioning however nothing jumped out. 

I finally noticed that it was only allowing me to transfer the conference call to a mobile phone and not to any other user like it would in the peer-to-peer session. I immediately checked the Phones list on the client that was not working and all the fields were blank:

Upon configuring the client with a Mobile phone:

I was then able to transfer the conference call to my mobile:

Solution:

In order to transfer conference calls to another phone, the phone number must be associated with the user’s account either by one of the telephone fields in AD, or by configuring the number within the client itself.