I set up 3 resource mailboxes on our Exchange 2003 server for booking meeting rooms, following a guideline from MSExchange.org. These resource mailboxes were created a couple of years ago, and always worked fine. For some reason all 3 of them stopped displaying their schedule when you try to book a meeting and I'm not sure why.
I configured my Outlook to log in as each mailbox (one by one) and verified the mailboxes are set to automatically accept or decline invitations. I also checked the permissions on each mailbox and Default and Anon were set to Editor on all three.
If I add a regular user to a meeting request I can see their schedule fine...I just can't see the meeting rooms. Also, the meeting rooms are accepting requests as when I log into the profile for the resource, I can see a number of meetings scheduled over the next few days.
The regular user shows a gray bar for open time and a dark blue bar when they have a meeting scheduled. The meeting rooms all display \\\\\\\\\\\\\\\\\ for every day.
As a test I set my Outlook profile to default to one of the meeting rooms and ran Outlook /cleanreminders, but that had no effect.