Is it possible to create the second All Rooms in Exchange?

Question

Hello everyone. We have 8 Exhange 2019 серверов. Last time, when users open their Address Book in Outlook, they are intermittently unable to select All Rooms, this error is displayed: There are not enough system resources available to complete this operation. The rest of the lists always work - Contacts, Global Address book, All distribution List, All Users and so on. The question is, is it possible to create a second All Rooms (albeit with the same name), so that users would have two All Rooms. Intuitively, they will figure it out and remember which All Rooms is correct and works. If I create a distribution group and convert it to RoomList, then users will have to do additional operations, first go to the Distribution List and only select rooms there, they will not want to do this and management will be against it.

I also wanted to ask how the All Rooms technology works? If I understand correctly, All Rooms is stored in Active Directory in the Global catalog, but some of the information is stored in Arbitration mailbox. I noticed that when I change or create a Room, the information changes instantly and it is unnecessary to update the Offline Address book and it is unnecessary to even update the client's Address Book.

I'm afraid to change anything with the current All Rooms because it will affect 5 thousand people and they will not be able to use calendars. But creating another All Rooms with the same name or, for example, All Rooms(2) and then giving access to a specific group is a good option.

Answer 1

Glad to know the issue has been resolved, thanks for sharing the solution so others with the same issue can easily reference it!

Since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others", I'll repost your solution in case you'd like to "Accept" the answer : )

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[Is it possible to create the second All Rooms in Exchange?]

Problem symptoms:

Users are intermittently unable to select "All Rooms" when opening their Address Book in Outlook with the error: There are not enough system resources available to complete this operation.

Resolution:

“I renamed these rooms to ISCSII characters (regular English), and it worked. After thinking about it, I went into the regional settings and set the language we use (Russian) everywhere, as well as the Region format. To do this, I had to install a language pack and overload, everything worked.”

Answer 2

Hello，

Welcome to our forum!

Regarding all rooms technology that you want to know about, it seems that your understanding is correct. It is the default address list, which includes all meeting room resources in the organization. It is one of the built-in address lists that comes with Exchange. It is not static but updates dynamically, so there is no need to update the offline address book or the client's address book.

Besides, you were wondering if you could create a second All Rooms in Exchange, that doesn't seem to be possible if you create it with the same name, as you mentioned you could try using New-AddressList to create as all rooms 2 or something like that with the recipient filter "Alias -ne $null -and (RecipientDisplayType -eq 'ConferenceRoomMailbox' -or RecipientDisplayType -eq 'SyncedConferenceRoomMailbox')". For more information, please refer to Create address lists. However, that is not the best sustainable solution.

Considering that you encountered the error when selecting "All Rooms": There are not enough system resources available to complete this operation, after research,it seems that there are other people who have encountered the same problem. In order to solve the problem, it is recommended that you first try the following steps and see if it works for you:

1. Try to log in to Outlook Web to see if it is normal.
2. If working fine, you may check this Microsoft article and complete all the steps: Insufficient memory errors and sent mail stuck - Outlook | Microsoft Learn
3. Run Outlook in safe mode (close Outlook, press Win+R keys, type "outlook /safe", press Enter) and check the results.

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