You cannot receive a chat room invitation in a Microsoft Lync 2010, Group Chat client.
This issue occurs because the lastInviteID value that is located in the local preferences is larger than the value of the lastInviteID that is located in the Group Chat server database. Therefore, the Group Chat server assumes that the client received the latest invitation, and does not send a new invitation.
To resolve this issue, install the following cumulative update:
2571550 Description of the update for Lync Server 2010 Group Chat: July 2011
The lastInviteID value on the Group Chat client is located in the following file: %appdata%\Microsoft\Group Chat\Group Chat Client\Preferences\username\Invitations
To verify the lastInviteID value, follow these steps:
Start SQL Server Management Studio.
Select the database for group chat.
In the dbo.tblPrincipal table , select the record of the user who cannot receive invitations and note the prinID.
In the dbo.tblLastInviteId table , select the record with that prinID from the previous step.
The lastInviteID value that is related to the prinID is the value for lastInviteID.