“The obscure we see eventually. The completely obvious, it seems, takes longer.” Edward R. Murrow

Indeed.

A few weeks ago I created a set of resource mailboxes, assigned delegates, and tested functionality. Everything seemed to be great. but then a few days later, the end users called to say that no one except the delegates could see events in the calendars for any of these new mailboxes.

I hadn’t done anything differently with these than I had with other mailboxes that I had created in the past, but I knew from experience that permissions on resource mailboxes can be flaky. Assigning the delegate in the Exchange Management Console should modify the calendar folder to give the delegates Editor permissions, but frequently I have to add those permissions manually using ExFolders.

The first thing I did was to confirm the problem. I’m not saying that end users make stuff up, but sometimes they’re description of what is happening is different than my description would be of the same events. First, I gave myself Full Access permissions to the mailbox and looked at the calendar to make sure there were events there. Then I removed my permissions and restarted Outlook. No events.

Next, I deleted my Mail profile and the cached Outlook data from the Local and Roaming appdata folders. Then I started Outlook and created a new Mail profile. After waiting for my mailbox to completely download, I still had the same problem: no events. For my third trick, I disabled the “Download shared folders” option in the account settings option and restarted Outlook again. No change. Next I disabled caching (nope) and then re-enabled caching (still nothing). So I tried different versions of Outlook.

In Outlook 2010 and 2013, I could open the calendar without error, but I couldn’t see any of the events that I knew were there. In Outlook 2007, I received this error when I tried to open the calendar: “You do not have permission to view this calendar.” In OWA, however, everything looked fine. I could see the calendar and all events. Very odd.

The error in Outlook 2007 led me to believe that the problem must be related to permissions or at least a difference in the way that the various versions of Outlook interpreted the permissions.

I checked the freebusy information and calendar folder permissions. They looked fine:

Clearly, it was time for something really drastic, so I exported the entire mailbox to a pst file so I wouldn’t lose any data. I set a password and enabled the AD account for the mailbox and created a Mail profile for it. Using MFCMAPI, I deleted the default Calendar folder. Next I opened Outlook using the /resetfolders switch, which rebuilt the Calendar folder, then I copied the calendar items from the exported pst file. Close Outlook, disable AD account, re-open Outlook under my own name, and…nada. I disabled the AD account again

I did some reading, asked around, did some more reading. After giving myself Full Access permissions to the resource mailbox again, I re-opened the resource calendar, opened one of the phantom events, and stared at my screen for about five minutes. Properties…attendees…date…time…show as… Wait…what was that about free/busy details? Show as: Free!? I switched the “show as” setting to Busy, and voila! Problem fixed.

D’oh! All that, and the problem turned out to be a feature. If all you can see is whether or not the resource is free or busy, then it’s not really a problem if that’s all you can see. The room delegates had been creating events by manually adding them to the calendar and setting the status of each event as “Free” instead of “Busy”. The calendar was showing everyone else exactly what they told it to show: nothing.

So… Nothing to see here, folks. Move along!