All iPhones could not access the Exchange server anymore and the Application Event log just filled with Event: 3005
Unexpected Exchange mailbox Server error: Server: [uuuu.uuuu.local] User: [Administrator@suuu.com] HTTP status code: . Verify that the Exchange mailbox Server is working correctly.
iPhone reports that it cannot attach to the server.
I had recently assigned an IP address to its second NIC and enabled it. It is a backup network so all backup traffic stays off the production network. I find these errors go away when I disable the NIC. I confirm that it only has an IP address and subnet mask assigned and it does not register itself with DNS..
Found the discussion below. One person mentioned changing the IP address the website uses to “All Unassigned”
I try this in IIS Manager. Right-click “Default Website” choose Properties, Web Site Tab, Change IP Address to “All Unassigned”. Everything now works fine.