Another one in the series of ‘blog this so I won’t forget about it later’ 🙂
So, apparently, it is no longer possible to configure the AddNewRequestsTentatively parameter on regular mailboxes. This option makes any new meeting request you receive to appear Tentatively in your calendar. Here’s the description we have for it on TechNet:
The AddNewRequestsTentatively parameter specifies whether to have the Calendar Attendant put new calendar items tentatively on the calendar. If the AddNewRequestsTentatively parameter is set to $false, only existing calendar items are updated by the Calendar Attendant.
It’s a nifty little feature, and it’s turned on by default so you probably didn’t even knew it’s customizable. In some cases however, you might want to turn this off – for example if you are receiving a lot of spam in the form of meeting invites. Or if it’s simply your preference to always manually update your Calendar items.
Anyway, so this was possible in previous versions of Exchange, and even in Exchange 2013 until recently. Here’s for example a screenshot from my Exchange 2013 CU1 box:
Unfortunately, it seems this was changed around the release of CU7 (and a bit earlier in the service), so now you are greeted with the following error message:
PS C:\> Set-CalendarProcessing pesho -AddNewRequestsTentatively $false AddNewRequestsTentatively can only be enabled on resource mailboxes. + CategoryInfo : InvalidData: (Pesho:ADObjectId) [Set-CalendarProcessing], ResourceOnlyException + FullyQualifiedErrorId : [Server=HE1PR03MB1340,RequestId=c83acce6-ba19-4459-88c8-176d0c9eb367,TimeStamp=9/19/2015 9:10:08 AM] [FailureCategory=Cmdlet-ResourceOnlyException] 102962F8,Microsoft.Exchange.Management.StoreTasks.SetCalendarProcessing + PSComputerName : outlook.office365.com
The workaround would be to convert the mailbox to Room one, set the option and convert it back. There’s a little catch here however – converting any type of mailbox to Regular one will set the AutomateProcessing option to None, in effect causing you more problems that it will solve (as there is no way to change this back to AutoUpdate via the regular Exchange management tools). So, time to accept the fact that this option can no longer be controlled server side and move on. You should still be able to configure this on the Client as detailed for example here, but that solution also has it’s downsides…
> converting any type of mailbox to Regular one will set the AutomateProcessing option to None, in effect causing you more problems that it will solve
What do you mean by more problems? What will happen?
Means that the Calendar attendant will be switched off for the mailbox, and meeting requests will not be processed automatically. As described here: https://technet.microsoft.com/en-us/library/bb123874(v=exchg.141).aspx
Note that this post is 2y old now, so things might have changed.