It might happen that a mobile device running an Android operating system is not being redirected properly by the on-premises AutoDiscover service, when the mailbox has been migrated to Office 365.
If your device is not redirected, the device prefix is not recognized by Exchange Server and therefore not being redirected properly. The new device redirect feature for Android devices was introduced in Exchange Server 2010 SP3 RU9, Exchange Server 2013 CU8, and Exchange Server 2016.
The following device prefixes are known to Exchange by default:
- Acer, ADR9, Ally, Amazon, Android, ASUS, EasClient, FUJITSU, HTC, HUAWEI, LG, LS, Moto, Mozilla, NEC, Nokia, Palm, PANASONIC, PANTECH, Remoba, Samsung, SEMC, SHARP, SONY-, TOSHIBA, Vortex, VS, ZTE
If the device prefix of your device is not part of the default list, you can add the prefix to the AutoDiscover web.config file.
Add the device prefix to the MobileSyncRedirectBypassClientPrefixes key in the appSettings node.
- Modify the web.config on each Exchange 2010/2013 Client Access Server and each Exchange 2016 server.
- After installing an Exchange 2013/2016 CU, the web.config must be modified again.
As always: Be careful when modifying application settings. Test such changes in a test environment first, if possible.
- Some Android devices do not redirect to Exchange Online
- Exchange ActiveSync on-boarding to Office 365
- Exchange HTTP ActiveSync Protocol: HTTP Error 451
You need assistance with your Exchange Server setup? You have questions about your Exchange Server infrastructure and going hybrid? You are interested in what Exchange Server 2016 has to offer for your environment?