Microsoft Exchange 2013
Here is the issue we are having. Users that have updated to IOS 9.0 experienced the Ghost email issue. After Apple came out with the 9.1 update users that updated and came into the office and got onto our wi-fi then experienced no email updating. We tried removing the account off the phone and adding it back but with no success. We would get an error saying it can not verify account information. I have found 2 work around's but The only work around procedure to work consistently is procedure 1 below. This only works if you have access to your server.
Procedure 1
1. Remove email account from phone
2. Reboot the exchange server
3. After reboot add account back to phone
Procedure 2 (This worked on one phone)
1. Open up Exchange ECP (https://<Server>/ecp)
2. Go to Recipients > Mailboxes
3. Select the persons account and on the right side, under phones and voice features > Mobile Devices, click View Details
4. Trash the mobile device so it has to recreate itself after re-authenticating with Exchange
5. Wait a while then try to add the account back. (took 2 hours for us before we were able to add the email account back. It was quicker to reboot the server)
Why does this work? I am unsure of right now. My guess is IOS 9.0 corrupted something within the users profile. So after updating to 9.1 and removing the account off the phone or the device from the user seems to resolve the issue. This is not a fix but a work around. IF anyone has a fix for this I would greatly appreciate the info.