Check your event log on the dashboard to see if there is a message regarding webmeeting
The problem you face means that the PBX cannot communicate with the webmeeting servers to inform them of the meeting creation, and hence you are trying to reach a meeting that does not exist because it was likely never created on our servers in the first place.
Check your event log on the dashboard to see if there is a message regarding webmeeting
Can you please confirm the following points?
Make sure your certificate is valid and not self signed.
Port 5001 or 443 is open for bidirectional communication with webmeeting.3cx.net
Make sure your extensions at least have a Name or a Last Name
Your extensions MUST have an e-mail for WebMeeting to work.
Make sure your PBX's FQDN is resolving properly. If not, after a long grace period it's WebMeeting meeting data will be deleted as you'd be considered inactive
Restart your 3CX System Service. This resyncs important data between your PBX and the WebMeeting server.