We have this problem, currentyl we have Lync2013 installation frontend plus EDGE, all wowkring properly includinf sip trunk, but we have one problem (i dont know if aftre last 2 updates).

When users try do conferecnce all internally is all ok, externaly too but only for 2 participant, when we try add 3 (that is outside office) than conference chnaged to ONHOLD status without any possible to chnage it.

No error logs in EDGE or FRONTEND, i think tjat is worked a we do now changes in infrastructure.

Thank Roman

How's the hardware hanging out?. I have seen this happening where there's not enough resources to process the meetings within the MCU.

Hi Roman,

As Thamara mentioned, you should check the Lync server performance.

If this is not the case, the only way that you can do is to check the logs (front end, edge, client).

Best regards,

Eric

Here you have mentioned that when trying to add 3 from outside office it changes to ONHOLD? does that mean you can still add people within the organization , the 3rd person is that a federated user you are adding or its an external number that you are dialing so that to get added to the conference.If this involves PSTN calls then  need to check Trunk configuration and also the GW logs if available. 

Sorry for delay in my aswer, i was on vacationI have an idea . it is any diffrence in Lyn2012 from o365 and standrd lync clinet for on-premise?

In lync log we have no psecific eror. Trunk is trough swisscom - separate line - directly connected to hyperv not trough firewall dedicated for SIp traffic

I have the same problem too. Current environment is co-existence between 2010 and 2013. Multi Video Conference with more two participants (all are already in the 2013 pool) always failed. OnHold status is also confirmed in my case.

Any update or possible solution for this issue?

Thanks and Regards,

Sully

Hi,

please run the following Lync PowerShell command:

Get-CsConferenceDirectory | FT Identity,ServiceID

In the serviceID Field,please check if any Identity has a blank ServiceID.

If so means it can belong to older Lync server installation that is not removed.

Then in Outlook,create New Meeting and click on Meeting option button to see if you get any error.If you do get error,please run the following command to remove invalid conferencedirectory:

Remove-CsConferenceDirectory xx Force

Where XX is number of Identity With blank serviceID.

Also run Get-CsConferencingPolicy to check value of max Meeting size