i've tried what seems like every possible combination of Resource Settings on the resource mailbox with no luck. The strange thing is that resource booking was working for a while. I've also granted the user full access permission to the resource mailbox. I have Outlook 2007 clients. What am I missing? Any help will be greatly appreciated.

Hi there, Could you provide more information about the issue you are encountering? Are you trying to add a delegate to the resource mailbox? You may enable the resource mailbox account and then edit the Resource Option in OWA. If there are multiple mailboxes, you may set a model and then copy the configuration to others. Refer to http://social.technet.microsoft.com/Forums/en-US/exchange2010/thread/567fc8cd-03ff-4ab9-80ed-26f83bbcfca2/Fiona Liao TechNet Community Support

One thing you may have a try is login to the mailbox and check the size of items with in the mailbox. You may connct to the mailbox through owa as you already have full access permission. If the mailbox is full, the booking confirmations willn't send out.Regards from www.windowsadmin.info | www.blog.windowsadmin.info

The mailbox is almost completely empty.

The resource will not automatically accept meeting requests from me. I have to login to the mailbox and manually accept. I've logged into the resource account using OWA and edited the Resource Options. I added my account with the "These users can schedule automatically if the resource is available. I added my account with full access permission. Here are the scheduling options I have set.

I figured out the problem and it was actually quite simple. The Microsoft Exchange Mailbox Assistants service was not running. About 1 minute after enabling automatic booking started working.