I'm currently installing a new installation of Exchange 2013 and am running into some strange behavior with ActiveSync. I currently have autodiscover working from every platform I've tried, but with mobile devices it's not consistent. I seem to be able to get it to work depending on the user, and new mailboxes I create work fine. I believe this would be a permissions issue but I'm not clear on where. I've tried to change permissions on the user object so the Exchange server can read and modify child objects, but that's not quite fixing it. Anyone have any suggestions where I should look? Even comparing the differences in user perms it's not clear if there is any difference at all.