On a new deployment of Exchange 2013, Active Sync is not working
- Mobile device fails to connect to mailbox “Unable to connect to server”
- You see the following error in the HTTP Proxy log:
- Also, in the application event log on your Exchange server you see Event ID 1053
Inheritance is disabled on the user account
As per this Microsoft KB article:
“The first time that a user tries to synchronize an EAS device, the Microsoft Exchange Server tries to create a container of the type msExchActiveSyncDevices under the user object in Active Directory Domain Services (AD DS). The Exchange Server then tries to change permissions on the container.