The messages in one mailbox re-sync every few minutes and mark all messages as unread even when the messages have been read and were marked as read before the re-sync. This only happens for one user and only for the Inbox folder. Does anyone know what causes this behavior? Thanks in Advance, Richard

This might be OST file problem ifoutlook is configured in Cache Mode. Find the OST Path: On the Tools menu, click E-mail Accounts, click View or change existing mail accounts, and then click Next.Click Microsoft Exchange Server, and then click Change.Click More Settings. Click the Advanced tab, and then click Offline Folder File Settings, check the path here.... Re-create the OST file:Delete it and open outlook again and outlook re-creates OST file automatically.

I deleted the OST file and the problem still exists. I'm not sure if it is related but this problem seems to have popped up after using Outlook Web Access.