Exchange 2010 SP1 Limits the Number of ActiveSync Devices You Can Synchronize

Some of us has a few more ActiveSync partnerships configured than the average user. Not because we’re able use all devices at the same time, or because we buy a new device every week. But because we test a lot of devices, fire up a couple of emulators, and generally have a number of devices passing through our hands.

After I upgraded my main Exchange 2010 box to Service Pack 1 and tried to do some testing I was met with a strict mail in Outlook Web Access informing me that I would not be able to establish more ActiveSync partnerships because I had 41 devices defined at the moment, as opposed to the maximum of 10 devices allowed. Say what? That’s right – by default Exchange 2010 Service Pack 1 will only allow you to have 10 devices.

The reason for this is that Service Pack 1 introduces a new feature called “Throttling”. It’s not really a bad idea, and it doesn’t apply only to ActiveSync either. It allows you to restrict how much resources any one user can consume so you don’t have resource hogs connected with 10 computers, 40 devices, and then some at a time. (Ok, maybe those numbers are a bit far-fetched but you get the point.)

I’m not going to go into details how this works, but you can control these settings with the Set-ThrottlingPolicy cmdlet.

To change the number to 50 (just a random number) run the following cmdlet:
Set-ThrottlingPolicy –EASMaxDevices 50 –Identity DefaultThrottlingPolicy_hex_string


To find out the “Identity” (that I shortened to “hex_string” above) to use you can run Get-ThrottlingPolicy first, and locate it there.

Ah, that’s better – now I can fire up another box full of devices and scatter around the house 🙂

13 thoughts on “Exchange 2010 SP1 Limits the Number of ActiveSync Devices You Can Synchronize”

  1. What was the behavior you were getting from your devices? I think I’m having that problem as I just tried adding a new device connection via iOS. It will add the account but not sync/connect to server to pull back email/contacts/calendars.


  2. The error Message you get on the client is usually some meaningless “not allowed to sync”. You should get a mail (in Outlook or on another device able to receive mail of course) informing you that you went over the limit.
    I can’t remember off the bat if my EAS MD utility catches it correctly – there should be an error code contained in the actual WBXML traffic.

  3. Thanks, for the tip.

    Under Android you’ll get a “maximum of devices on network” error.

    You have to wait 15-20 minutes after the script is ran before you can add a new device.

  4. Didn’t work for me. SBS 2011:

    PS C:\windows\system32> Get-ThrottlingPolicy
    The term ‘Get-ThrottlingPolicy’ is not recognized as the name of a cmdlet, function, script file, or operable program.
    Check the spelling of the name, or if a path was included, verify that the path is correct and try again.
    At line:1 char:21
    + Get-ThrottlingPolicy <<<<
    + CategoryInfo : ObjectNotFound: (Get-ThrottlingPolicy:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException

  5. I haven’t got an SBS system in reach, but I tested on a plain Exchange 2010 box. Get-ThrottlingPolicy still works. However it only works if starting the “Exchange Shell”, not the regular Powershell. (Which will probably work if one imports the correct module.)
    Which of the shells did you fire up?

  6. Well, being a noob didn’t help. Tried from the Exchange management console, that helped !

  7. Hosted Exchange should also have this policy available, but whether it is available to you or not depends on the hoster. Preferably they should have an admin panel for this, but if that’s not an option remote Powershell might be.

    You would of course need to have the proper permission to perform the task, and you’d also need to know the endpoint to shell into. The hoster should be able to provide you with the necessary details.

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