Hello, We are running Exchange 2007 SP2 in CCR mode on 2003 SP2 x64, and I am getting a strange error, pasted below, on one of our mailbox servers. There don't seem to be any instances of this error with error code 0x8007045a that I can find documentation for (and anything I can find on EXCDO 8217 in general also hasn't helped). I think error code 0x8007045a might to have to do with DLL problems of some sort, but I'm unsure how to troubleshoot further. This error is also happening on multiple mailboxes and multiple appointments around 40 times a day. Anyone have any ideas? Thanks! Event Type: Error Event Source: EXCDO Event Category: General Event ID: 8217 Date: 7/6/2011 Time: 11:53:29 AM User: N/A Computer: SERVERNAME Description: The processing of the recurring appointment with the subject "Subject Here" in mailbox: Mailbox Here failed with error code 0x8007045a.

Delete the appointment and recreate it.Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

Hi Ed, I have already tried this, but gave up when I looked further back in the logs and saw that there are ~60 or so different appointments that give this error within the past week, and it keeps occurring on new appointments, too, so this isn't really a viable option. I'm the only Exchange admin at my company, and I can't afford to spend an hour every day calling users, explaining the problem to them, and having them delete and recreate their appointments. Do you have any other suggestions?

I'm sorry, I have no experience with that problem.Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."