Okay this is a weird one . . . Our organization has multiple users that use the iphone to connect to exchange. We have Exchange 2003 SP2 BTW. One user in has a problem syncing their calendar to their iphone. Thing is though, it works 99 times out of a hundred or so, but reliably fails sometime in between. When this happens, the appointment in question won't sync with his iphone, and he gets a 500 "internal error" when he tries to access it with OWA. They open up fine in Outlook though. The events are created in Outlook (2007). A bunch of things have been tried . . . they have changed this user over to a new verizon iphone. Same problem, so we know it's neither ATT, nor verizon. They tried asking him not to create appointments from the phone and to use Outlook and that didn't work. The crazy thing is that it's happens so sporadically. His mailbox isn't the largest in the company, and he doesn't have the highest number of items in it as compared to other employees who DON'T have the problem. I wondered if it could be an error in his mailbox. He uses it a TON, but I haven't seen anything on the event logs to indicate that. Just wondering if y'all might have any ideas what could be causing this, and a way to fix it, or even a place to start? -S

Quote: “he gets a 500 "internal error" when he tries to access it with OWA” Please check if the issue also appears when you drag this meeting into another working iPhone user’s calendar and synchronize his/her iPhone Quote: “I haven't seen anything on the event logs to indicate that” You have checked in the application log on the server? After reproduce the issue, please check if there’s any related traces in the IIS log except the error 500 Please also move the mailbox of the problematic user into anther mailbox database, which could fix certain logical corruption on the mailbox Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.