We can add the phones to an ongoing online meeting, and audio and video works fine too. We can call the phones directly to their Skype for Business IDs and audio and video calls work flawlessly. On the application log of the 8800 I found the following lines that seem to be relevant:ġ108104154|app1 |5|00| Input Link(***/***/Y1DGVMYY?conversation-id=aE4u6cRbt subject=***) Output isCallLogRejoin(0)ġ108104155|sip |4|00| no MedSessHdl found Since the first week of October 2016, none of these phones can join Skype for Business online meetings from the 'join' button or from the calendar alert.

We have two Trio 8800 and a few VVX400 provisioned with Skype for Business cloud accounts.