We often want to make quick announcements to our group of 20 people using Office Communicator, so we highlight a group of contacts and start a new IM session. However, only a maximum of 10 people are able to join the conversation; after the maximum number of people join, all other invitees get the message:
Cannot connect to the conference because it is full. Contact the conference leader for more information.
Is there a way to increase the maximum number of participants?
If you go into your forest, properties, global properties, meetings tab, go into one of the profiles. The maximum meeting size directly ties into the max people who can be in a multiparty IM at the same time as well. It's tied into the initiator of the session as well...so whoever started the IM (whatever his/her policy is set to) defines how many people can enter the multiparty IM.
I had the problem because I initially set it to 10 because I thought this setting was related to Live Meeting only. Live Meeting uses more bandwidth and we don't have a ton so I restricted it. People where then having problems sending IM's to distribution lists. After testing and once I figured this out I had to bump the number up.
This number also only comes into play when users are connected......so if I restict to 15 and I have 20 people in my DL, but 7 are offline, I'm really only going to connect with 13....which is under the 15 maximum meeting size.