Apple acknowledges iOS 6.1 Exchange bug and has identified a fix

Apple acknowledges iOS 6.1 Exchange bug and has identified a fix

Summary: It's been over two weeks since Apple released iOS 6.1 containing a significant Microsoft Exchange bug. Since Apple hasn't released a fix some IT administrators are blocking the devices from their servers.

TOPICS: Apple, iOS, iPhone, iPad, Microsoft
iOS 6.1 Exchange bug becoming a credibility issue for Apple - Jason O'Grady

On January 28 Apple released iOS 6.1 and with it, a significant bug that's been giving IT administrators headaches. Almost immediately after 6.1 was released Microsoft Exchange admins began noticing that iPhones and iPads running 6.1 were causing "excessive logging" on the server.

The problem has been traced to Apple code that calls ActiveSync to synchronize a user's Exchange mailbox and calendar events. According to Microsoft iOS 6.1 was responsible for the "rapid growth in transaction logs, CPU use, and memory consumption in Exchange Server 2010 when a user syncs a mailbox by using an iOS 6.1-based device."

Enterprise users are being warned by their IT departments not to use iOS 6.1 devices with corporate servers. Symptoms included email downloading slowly, duplicate calendar items and the inability to delete, edit or move items. Some companies are asking iOS 6.1 users not to connect to their servers, while others are actively blocking iOS 6.1 -- even company-issued devices -- by adding a simple rule to /microsoft-server-activesync which throws a simple "The server refused connection" on the device. 

if {[HTTP::header "User-Agent"] matches_regex {^Apple.*1002.*}} {



The bug is causing some corporate IT departments to block their own devices from their Exchange servers. 

Microsoft's technote offers three workarounds for the bug:

  1. Remove the Exchange account from the device
  2. Create a custom throttling policy for iOS 6.1 users
  3. Block iOS 6.1 users

Although Microsoft states that it is "working with Apple to investigating this issue" Apple has yet to post a fix more than two weeks after iOS 6.1 was released. At a minimum, Apple should offer affected 6.1 users a way to roll back to iOS 6.0 so that they can continue to get their email and calendars from corporate Exchange servers. Instead, IT administrators are being forced to take matters into their hands and block Apple devices. 

Update: As this story went live Apple posted a knowledgebase article acknowledging the issue and providing more detail:

When you respond to an exception to a recurring calendar event with a Microsoft Exchange account on a device running iOS 6.1, the device may begin to generate excessive communication with Microsoft Exchange Server. You may notice increased network activity or reduced battery life on the iOS device. This extra network activity will be shown in the logs on Exchange Server and it may lead to the server blocking the iOS device. This can occur with iOS 6.1 and Microsoft Exchange 2010 SP1 or later, or Microsoft Exchange Online (Office365).

The article goes on to offer a workaround, stating that you can avoid this bug by not responding to an exception to a recurring event on your iOS device. The workaround is to disable then reenable the Exchange calendar on your iOS device:

  1. Go to Settings > Mail, Contacts, Calendars
  2. Select the Exchange account from your Accounts list.
  3. Turn the switch for Calendars to OFF.
  4. Wait ten seconds.
  5. Turn the switch for Calendars back to ON.

Apple goes on to say that it has "identified a fix and will make it available in an upcoming software update."

Topics: Apple, iOS, iPhone, iPad, Microsoft

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  • Apple hasn't acknowledged this issue???

    But Apple has acknowledged this issue-
    • not in the mainstream press

      its just an update without details for the man on the street
  • Shame!

    I would say the author is Obligated to retract this article or acknowledge that it is wrong!
  • Duly noted

    Update for the story is in the queue.
    Jason D. O'Grady
    • Credibility?

      "Update: As this story went live Apple posted a knowledgebase article acknowledging the issue and providing more detail:"

      As this story went live? I don't think so. The KB article was published many hours before your article.

      If you are going to write something that is a direct attack on a company's credibility you should make sure your facts are up to date otherwise it's your publication's credibility that is in question...
      • A few hours compared to a few weeks?

        So the auther missed an Apple article that was posted nearly the same time they were posting their own article. It does not invalidate the fact that Apple did not acknowledge the bug for several weeks.

        A bug that clipped users ability to use work email and/or crippled email servers for other users.

        Two weeks for a bug like this is an eternity for corporate space.
      • LOL.. It's caused hassle for two weeks but you split hairs on this...

        Come on man... get a grip on reality. Apple lay low for two weeks and you think the guy will double-check just before he presses the upload story button. You're not seriously saying Apple just found out; please don't suggest they haven't been scurrying around code for umpteen days. Next you'll be blaming microsoft for a clash that Apple helped them find in a 'stable' product. Brilliant laugh though.
  • You Apple fanbois are too funny!

    Three posts about how poor widdle Apple was wrong by the author yet NOTHING about the topic of the article. You guys really need to stop identifying yourselves with some corporation that cares nothing about you.
    • The story was inaccurate

      It's no different from the articles that mistakenly reported the capacity of the Surface Pro.
      • I understand that.

        "It's no different from the articles that mistakenly reported the capacity of the Surface Pro."

        Uh yes, it is different. The inaccuracy had little to do with the problem of iOS 6.1 having problems with Exchange servers. The inaccuracy of Apple not having responded to the issue was nothing more than a side show. You guys were more concerned about the author being in error about this than the topic of the article. The author even updated the article to correct the inaccuracy and someone still jump on his case.

        As I said: You guys really need to stop indentifying yourselves with a company that cares nothing about you.
      • It is very different

        This article accurately details Apple not acknowledging this bug for 2 weeks and there being a very real bug in iOS6 causing the issue. So the author missed Apples KB article that was posted almost the same time they were posting this article. At least it didn't take the author here 2 weeks to admit, let alone correct, that there was a mistake.

        Articles that incorrectely detailed surface storage were referencing information given from a Microsoft employee. The failure of those articles rests with Microsoft.
  • Great Fix!

    TURN IT OFF! Of course it's going not going to work right if it's turned on - it's an Apple product!
    • Nice trolling!

      Wow nice trolling comments!
    • Sad. But true.

      x I'm tc
    • That is not the only solution

      But it is one that is offered. Here is what MS really has to say.

      1 and 3 were not options so we used option 2 in combination with the Apple recommendations and things have calmed down.
  • But ...

    It just works - or maybe not!
  • Longer than iOS 6.1

    There's been at least an Exchange bug in iOS around way longer than 6.1 in which all-day events on the Exchange calendar do not sync correctly and the net result is like a zillion new draft requests for the same meeting. Apparently, the incorrect sync by iOS causes exchange to make a new meeting request each time iOS tries to sync an existing all-day event from Exchange. It's way annoying, and if enough people are syncing their Exchange calendars to their iPhones/iPads, it can easily bring down the Exchange service.

    I've been able to work around this by simply going to the Exchange account in iOS's Mail/Calendar/Contacts settings and turning off Calendar syncing for the Exchange account. This way, I can at least still continue to get mail messages. Granted, this isn't a big loss for me, because the handful of things in my Exchange calendar that need to exist on my phone can easily be copied manually into my iCloud calendar, but for someone who has higher traffic in their Exchange calendar, this could be worse.

    Also, in an apparently unrelated observation, iOS 6.1 does not seem to be producing any kind of alert notifications for Tasks and Follow-up flags with reminders for synced Exchange accounts. Frustratingly, I've missed a number of reminders this way before I realized if I wanted my phone to remind me of something, I'd have to manually enter it into iCloud.
  • good for blackberry

    it this persists then blackberry may get some of the iphone share back
  • Apples New Official Fix

    "All users will be able to avoid Exchange issues by holding their devices perpendicular to their wallets and rotating counterclockwise 30 degrees before they hit send"
  • Similar issues pre-date iOS 6.1 and/or Microsoft Exchange 2010 SP1 or later

    I've seen similar behavior several times before, and in December, traced it to runaway devices running iOS 6.0.1 and 6.0.2 talking to Exchange 2003...