Why all Exchange ActiveSync experiences aren’t the same… and how to know what you’re getting

One of the most frequent questions I get as the Product Manager for Exchange ActiveSync (EAS) is for a list of EAS-enabled devices customers can use for mobile email and what functionality they support. This is often a difficult thing to provide since Microsoft licenses patents (which are Microsoft’s Intellectual Property) to EAS licensees. Along with licensing our Intellectual Property (IP), we provide public access to the Exchange ActiveSync protocol documentation. IP licensing does not include Microsoft writing the code for the licensee’s devices or services— that would require Microsoft to write the code for each of the many platforms licensees have and also make us update it every time those platforms were updated.

As part of their implementation, each licensee makes the decision about what parts of EAS they want to implement and how they might best want to do it with their platforms. We always try to work with our licensees to help them create great experiences, but at the end of the day it’s up to each licensee to decide what features they want to make available to their customers. Since each licensee does their own implementation of the EAS protocol, many people ask if there is a list of features implemented by each licensee, so that they can determine which devices meet their organization’s needs. A helpful chart of some of the more common implementations (Windows Phone, Nokia (Symbian), iPhone (iOS), Palm Pre (WebOS), Android, etc.) can be found in Comparison of Exchange ActiveSync Clients.

You may notice that this chart is posted on Wikipedia. This is another way that information is available to the Exchange community, and since it’s a Wiki, you’re all able to contribute!

With always updating software, new devices coming out, and a growing number of EAS licensees making options available, EAS devices are a particularly hard thing to keep track of. We think this is an easy way for each of you to share the information you discover with each other, and a way of building upon some of the great work some of you in the Exchange community are already doing (here’s an example). We hope this can be a useful resource to you in managing mobile devices on Exchange and that you are able to help contribute to the benefit of all folks managing Exchange-connected devices.

Adam Glick
Sr. Technical Product Manager

Comments (14)
  1. Leo Jacob says:

    What’s Microsoft’s hypothesis on why _no_ EAS licensees seem to implement task syncing?

  2. Adam Glick says:

    @Jake If you look at the table you may notice several licensees do implement task syncing.

  3. Baron164 says:

    I’m surprised nothing syncs Notes at all. Is that an Exchange limitation or a device limitation?

  4. Adam Glick says:

    @Baron164 This is not an Exchange limitation; no client has chosen to implement this feature yet.

  5. andrewj says:

    @Adam Glick.  HUGE ‘fail’ that it has never been available in Windows Mobile – when Blackberry has had Notes sync forever.

    Do you know Notes sync will be available in the Windows 7 Phone EAS client? PLEASE :-)

    Interesting post and link to chart.

    Thanks Adam!

  6. Jonas Back says:

    One thing I find strange is that MS didn’t implement some kind of "check" to see if the mobile phones are lying or not. Most common example when the iPhone 3G was lying about encryption and when they implemented the "proper" way to answer NO when it’s actually not encrypting after that iPhone OS update – they were turned down by the Exchange server.

    Sure, I guess it’s up to the EAS licensees to implement the protocols correctly but if they don’t, I think MS should be more serious and contact them and say "make it right or you loose the license".

    Because if I disallow WiFi, I really want to make sure ALL mobile phones really disable WiFi, I don’t want to sit down and test every brand it is out there. If I didn’t care about any security settings – I would simply click Allow non-provisionable devices". The mobile phone vendor often don’t have a clue if you ask them – "we support some EAS" they say. I think it would help if MS would help out here to make sure it’s done correctly. Don’t ask me how though. I’m just got tired to trust the mobile phone vendors :)

  7. Daniel Melanchthon [MS] says:

    @AndrewJ: Does RIM support syncing notes over the air or through the Desktop Manager? I believe with Windows Mobile you can sync notes using Windows Mobile Device Center.



  8. Riccardo says:

    What would be nice to see is what clients support the SRV record for auto discovery

  9. andrewj says:

    @Daniel Melanchthon [MS]

    RIM *certainly* supports Notes sync OTA.

    (I think it can also be done via Desktop Mgr – but in my experience Desktop Mgr is typically not rolled out in corporate environments).

    PLEASE can somebody encourage the WP7 folks to put Notes (and Tasks) sync in the WP7 EAS client?  That would be a BIG plus for WP7 verses iPhone/Android.  And heck – its Microsoft – y’all SHOULD have the best EAS support :-)  Thanks!

  10. Jason says:


    A few years back you had a blog post entitled "Securing Exchange Data from Unapproved Mobile Devices" where you recommended to block devices by User-Agent in ISA rather than by EAS policy due to the variability in client EAS implementations. (http://msexchangeteam.com/archive/2008/09/05/449757.aspx) Is this still a recommended best practice for Exchange 2007 SP3? At the moment, all Android devices share the same User-Agent, so this method is effectively an all or nothing approach.

  11. Dean S says:


    YES! You are 100% correct in your comments.  Blackberry supports notes/tasks sync over the air for a long time.  Completely agree that MS has a huge win if they sync those in WM7.   If not, then it is no better than Apple.  It needs to be done via wireless, and not a local desktop connection.   This is the #1 complaint I get from our Blackberry users that have made the switch over to iPhones.  MS OS with a MS Sync technology should be the best compatibilty not second best in fuctionality.

  12. ThomasJEdmond says:

    ya that’s right

  13. sabasigh says:

    I am testing my Exc2003->2010 migration and had a question on OWA segmentation. I modified the Default OWA policy to have EAS disabled so a majority of my users cannot manage their phones. I then assigned that policy to some recipients.

    However, when they login, they still have the Phone section. Disabling Text Messaging portion in the Default policy works but not the Phone.

    I would rather not disable this on the OWA virtual directory as I need this to manage all phones.

  14. Soundbite says:

    When in the world is the Exchange team going to clean up the Notes function? This is an extremely useful feature that is simply annoying not to enable. (1) Update the OWA client with a New Notes post form. (Good grief–how hard can that one be? Just title and text fields!) (2) Better document ActiveSync’s synchronization of Notes. It’s aggravating that they’re just overlooking such a simple and useful part of their software that’s been there practically since day 1!

Comments are closed.