Have a strange one here.
Exchange 2010 with Outlook 2007 clients. Mix of cached mode and online mode workstations. All servers have latest service packs, as well as latest service pack on office.
The issue is that a random items WILL send by the item will stay in the Outbox. The item will send and will also end up in the sent items. The only way to get rid of the outbox items is to manually delete them. All the research I have done point to Anti Virus exclusions not configured correctly on Exchange servers. I have got them configured correctly.
Anyone else have any pointers or suggestions on where to start looking?