This issue occurs because room lists are a special kind of distribution group. This group requires a specific configuration so that it is visible as an option in Outlook for users as they move to vNext.
Room lists contain room mailboxes or mail users who represent room mailboxes in the legacy dedicated environment. These lists let administrators organize conference rooms, for example, by region or building. Users can select a specific room list in Outlook to view available rooms without having to add each room mailbox individually to a meeting request.
In the legacy dedicated environment, room lists are created by creating an on-premises distribution group, and then letting the group sync to the managed environment. An administrator can convert a distribution group to a room list by using the Set-DistributionGroup
When you transition to vNext, you should specify a room list and resource mailboxes (room and equipment). To do this, set a particular recipient display type and the on-premises recipient type details attributes that will be synced to vNext. Room lists can contain only room mailboxes or mail user objects that represent conference rooms.
On-premises distribution groups that are room lists and objects that represent room mailboxes should be set to have the following recipient display type (Active Directory property msExchRecipientDisplayType
) and recipient type details (Active Directory property msExchRecipientTypeDetails
). The msExchResourceMetaData
property is also requested in vNext for room and equipment mailboxes.
|Room mailbox||7||128||ResourceType: Room|
|Equipment mailbox||8||128||ResourceType: Equipment|
The room and equipment mailboxes must be mail-enabled in vNext. In Azure AD Connect, a mailNickName
property value (alias) is required.
To check room or equipment objects in vNext, run the following cmdlet:
Get-Recipient <SMTP address of room or equipment> | ft ResourceType
To check on a room list in vNext, run the following cmdlet:
Get-DistributionGroup <SMTP address of room list> | ft RecipientTypeDetails
To check all members of a room list in vNext, run the following cmdlet:
Get-DistributionGroupMember <SMTP address of room list> | get-recipient | ft primarySMTPaddress,resourcetype
If all rooms are corrected and the distribution group isn't converted to a room list, you must force Azure AD to retry the distribution group conversion to a room list. Do this by using one of the following methods.
Method 1: Remove the distribution group from Azure AD to be resynchronized by Azure AD Connect
To force a resync of a group, run the following cmdlet in Azure AD PowerShell to remove the group from Azure AD. Remove-MsolGroup
is a cmdlet that’s part of the Azure AD PowerShell module. For more information about Azure AD PowerShell module for PowerShell cmdlets, see Azure Active Directory cmdlets
More information about this command can be found at Remove-MsolGroup
. The ObjectID
property can be found by running the Get-MsolGroup
cmdlet. After the ObjectID
property is removed from Azure AD, it will be resynched the next time Azure AD Connect runs, and it will be synchronized to Exchange as a room list.
Method 2: Change the msExchRecipientTypeDetails property
Update the value of the msExchRecipientTypeDetails
property to 256
, which represents a distribution group. Wait for Azure AD Connect to sync the change. Then, reset the msExchRecipientTypeDetails
value to 268435456
. When the change is synchronized to Exchange vNext, the distribution group should be converted to a room list.