Exchange 2010 Allowing More ActiveSync Devices

In Exchange 2010, the maximum ActiveSync devices allowed by default is 10.
If you happen to have users who have tons of devices that connect to Exchange, you can set a Throttling Policy to allow more devices, then apply that policy to their mailbox(es)...all with PowerShell.

Fire up the Exchange Management Shell, and run:

New-ThrottlingPolicy -Name IncreaseEASMaxDevices -EASMaxDevices 50 - EASMaxConcurrency 50

**Note** In the above command I've set the max to 50, but you can set it how high you want. I gave the policy the name "IncreaseEASMaxDevices" but you can name it what you like.

Then Run:

Set-Mailbox "username" -ThrottlingPolicy IncreaseEASMaxDevices

**Note** Change "username" to the mailbox you want to apply the policy to.

Wait a few minutes for the policy to replicate and then try to add more devices for the user(s).