Is there any limitation of room list distribution group?

[Róbert Formódi]

Hi!

Our custumer has some room list based distribution groups one has 124 room mailbox members.The Room Finder of Outlook (2010,2013,2016) is not able list or expand only this one distribution group with 124 room mailboxes other dls with less room mailboxes are working fine.The suggested times menu says when you choose this dl the "Suggestion are not provided because there are too many attendees". Did anyone met such type of issue? Is there any members limitation of room list distribution group from desktop Outlook client view? With OWA all dls are working without any problem. Our customer has Hybrid Exchange 2010 with Adfs and Adconnect.

[#2]

There are some forum posts mentioning 125 member limits for Outlook, I guess something similar is in effect here. Best way to confirm this is to open a support case.

[#3]

Thanks! Now only with 99 room mailboxes working fine. So the limitation is it seems 100 attendees.

[#4]

Guess they changed it with the recent versions. If you want authoritative answer on this, contact support.

In any case, having to browse between 100 rooms in the same list is hardly convenient, you should consider partitioning it to smaller ones.

[#5]

Yes, there is a limit of 99 (less than 100) in a Room List in Outlook. This limit does not apply to OWA.

https://support.microsoft.com/en-hk/help/4041212/can-t-view-available-rooms-after-selecting-room-lis...

This limit appears not to be the number of rooms in the room list but the sum of the attendees and the number of rooms.
93 rooms + 6 attendees works fine
93 rooms + 7 attendees hits the limit.