Suddenly IMAP can stop working on your server. As you look through your setup, you will find, that it’s still configured correctly, and the service is running! – So what could be wrong?
Exchange have since version 2013, used Server Component States to granular control over the state of the components that make up an Exchange Server .
When theese are not working as supposed (Read=inactive/offline!), the service that lays behind, stops working, even though you find it “Running” in Services manager.
Here we will troubleshoot the IMAP service, which has an underlaying IMAP.Proxy, so let’s head to Exchange management Shell:
So why this happens, can be difficult to know, as theese are ADAccess related, it could be that one or more DC’s are offline or have been rebooted, network problems or other issues. But here is how to fix it 😉