Old Exchange Flaw Persists in iOS 7

Exchange ActiveSync Connections From One iPhone 5 Running iOS 7.

Exchange ActiveSync Connections From One iPhone 5 Running iOS 7.

Starting last December, and continuing in March of this year, we talked about a series of symptoms that often arrive hand in hand, sporadically, on Apple devices running various revisions of iOS 4, 5 and 6, up through 6.1.3.  Those symptoms include devices running warm to the touch or even hot, a battery that may drain significantly faster than normal, and spikes in cellular data use of up to ten times the user’s normal pattern.  While this trio of symptoms may well have more than one culprit, the many instances that I’ve personally witnessed have since been reduced to a single common cause.  One with a quick solution.

If you’d like to read the years-long chain of events in order, including documented interactions with Apple along the way, you’re welcome to follow these links to part 1 and part 2 of the story.  Today’s entry is the third – but not the final – installment.  In the interest of time, we’ll try to get right to the point.

For All Of Us
If your iPhone, iPad or iPod touch ever begins running warmer than normal, or the battery drains twice as fast, or you get sticker shock on your next cellular bill, you’ll obviously want to quickly determine the cause.  Fortunately, with iOS 7, this is easier than ever before.  Begin by navigating to Settings > Cellular.  Scroll down, and you’ll see data usage for native and 3rd-party apps directly under each application’s names.  But don’t stop there.  Also navigate into > System Services, and observe your usage here too.  If your device connects to your company’s Microsoft Exchange e-mail environment, don’t be surprised to see a high number next to Exchange Accounts.  And if you do, read on.

Cellular use stats are a good way to identify any application working overtime.

Cellular use stats are a good way to identify any application working overtime.

For Microsoft Exchange Users
As we alluded to earlier (after giving it away in the title, lead graphic and caption), virtually every instance of heat + battery drain + runaway data use that I’ve personally witnessed has been the result of a sudden-onset problem syncing a Microsoft Exchange calendar.  When an iOS device encounters an error syncing an Exchange calendar, it simply retries.  In fact, it retries every couple of seconds or so, nonstop, 24 hours a day, forever if you let it.  Unfortunately this is nothing new.

This past weekend, an executive’s iPhone 5 (on Verizon) and his iPad 2 (Wi-Fi only), both running iOS 7, began exhibiting runaway connections to my employer’s Microsoft Exchange ActiveSync server.  The user upgraded his iPhone 5 to iOS 7.0.2 over the weekend, but the problem persisted.  In one 24-hour period, his iPhone checked in with our server 45,009 times, while his iPad connected 55,547 times.  Normally we’d expect to see a single device connect a few hundred times per day rather than tens of thousands.  After notifying the executive this morning, and asking him to perform the following fix, his problem went away for the time being.

If you think this may be happening to you, but aren’t sure, you might consider contacting your company’s IT Department or Microsoft Exchange Administrator.  We’ll talk about what he or she can do in the next section.  Having said that, the potential fix is easy, non-destructive, and you can try it out to see if it solves your problem.  As illustrated below, you’ll simply navigate to your Exchange account settings, turn your Calendars off, and then turn them back on.  While one step, “Delete from My iPhone”, sounds ominous, you’ll get your calendar entries back when you re-sync with the server.  Further instructions follow in the next caption box.  Please read and re-read them.  And use them at your own risk.

On your device, select Settings > Mail, Contacts, Calendars > (your Exchange account). Turn off ‘Calendars’ and then ‘Delete from My iPhone.’ Wait thirty seconds, and turn Calendars back on.

On your device, select Settings > Mail, Contacts, Calendars > (your Exchange account). Turn off ‘Calendars’ and then ‘Delete from My iPhone.’ Wait thirty seconds, and turn Calendars back on.

For Microsoft Exchange Administrators
Keep an eye on the IIS log files on your Exchange ActiveSync server on a regular basis.  By doing so, you may be able to identify a runaway iOS device before the users even know what’s going on.  In larger environments, you’ll likely use automation and alerting tools to bring runaway devices to your attention very quickly.

For Apple
The fact that this runaway connection problem has persisted now across four generations of iOS is a bit ridiculous.  I’ve seen no Android devices exhibiting similar behavior in our environment, leading me to believe that it’s technically possible to engineer something that doesn’t do it.  Common sense suggests setting some sort of timeout; a maximum number of retries before abandoning a particular calendar entry update.  Last Spring I hoped that Apple would fix this situation with the next incremental release.  We now know that they’ve failed to address it in their next major release, iOS 7.  And that leaves all of us to live with the problem, monitor it, and execute this fix whenever necessary.

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  1. Robert Parks Robert Parks says:

    We’ve since had an iPhone 4s running iOS 7 (Apple-iPhone4C1/1101.465) begin exhibiting this behavior as well, connecting to our Exchange ActiveSync server 59,032 times in a single day.

  2. Interesting and succinct article – thank you. My iPhone 4S has exhibited the exact same symptoms you list and my Vodafone bill has gone through the roof because of it. I was searching for poor battery performance before I saw the bill, but now suspect this Exchange issue is the reasone. I hope therefore you have provided the solution I need. In a space of approximately 1 month it appears the Exchange Accounts under System Services has used 1.2GB of data…

  3. Hi there, I’m neither an admin nor am I using my phone in a corporate environment. But I do have my outlook.com account synced with my IOS 7 phone. Yesterday I gladly read your blog entry and deactivated the calendar component and reset the data usage statistics. Only 8 hours later, “Exchange Accounts” used another 90 MB of data. So I figure it might not only have to do s.th. with the calendar. I then also deactivated contacts, mail, tasks and again reset the usage statistics. As of now “Exchange Accounts” does not even show up in the statistics. I’m planning on reactivating each component every 3-4 hours and see if the problem persists. Can any “retail” customer confirm this behaviour? The disadvantage for me is, that I cannot go to “my” administrator and ask him to look at my accounts’ logs though…

    • Christopher says:

      Bert. I am using active sync for google mail, calendar and contacts. Having backup and restored my phone the issue persists and I cannot stop the requests or it running hot. Trying to turn off calendars does nothing and just hangs. Has anyone got a further idea on what I can do to fix this email account. All my other accounts are fine.

  4. ###### Update to my earlier post ######

    I have found the mail component of my outlook.com account to be responsible for using a big amount of data.

    Luckily, the problem has been resolved. The solution was to completely delete the outlook.com account from the device and re-add it. What was different from when I added it in the first place was that there was an explicit option to add outlook.com mail accounts. Before I added it using the “add an exchange account” option.

    I still monitor the data usage of the exchange accounts in the device preferences. Until now there has been no unusually high traffic.

    Maybe this is helpful for some people.

    • Christopher says:

      I’ve had the same issue with active sync for google/ mail/calendar/contacts. A backup and restore didn’t fix it and I don’t know what else to do to fix it. Since I am a personal user I wondered if anyone else had any tips on what I could try?

  5. We had this issue at our company and have recommended that our users contact their cell providers to get the data charges reversed that this has been causing. To date, we have had success in all cases where the charges have been shown to be due to the iOS version causing runaway calendar updates.

  6. Robert Parks Robert Parks says:

    We’ve now seen runaway calendar sync behavior on a 4th generation iPad running iOS 7.0.4 (iPad3C4/1102.55400001), which connected 75,436 times in a single 24-hour day.

  7. I have had this issue on my iPhone 5 with 7.0.4 and resolved it by deleting the account off my phone and setting it up again.

    I had 1.1 GB usage and my device was hitting our exchange server thousands of times a second between 3 devices (the two below).

    Interestingly one of our devs has a Windows Phone and a Surface tablet and had the same issues. He performed the same fix and it has worked so far.

    It actually crashed out our server last weekend as the log files got so bad.

  8. We’re experiencing this big time here…I just had to re-sync 6 devices due to dying batteries and Exchange transaction logs going thru the roof. May have to reconsider our IOS device strategy soon because I can’t keep doing this every day.

  9. Thank you. You saved me money trying to get my data under the monthly limit.

  10. Thanks for a great series of articles concerning this problem. It happened to me a couple of months ago and I ended up doing a factory reset. Not a very nice “solution”. This is why I really got my hopes up when seeing that simply disabling the Calendar sync would do.

    I sync three calendars to my iPhone 5S (iOS 7.0.5). Two Exchange accounts from difference servers and one Gmail. As it turns out I can’t turn off calendar sync on any of them. I can’t even remove the accounts themselves. The phone tries forever and them finally times out. Anyone here who has had a similar issue and maybe even found a solution?

    The power assertion timeout: https://dl.dropboxusercontent.com/u/26840/iOS_power_assertion_timeout_DataAccess_Exchange_related.png

    The preferences timeout: https://dl.dropboxusercontent.com/u/26840/iOS_preferences_timeout_turning_off_calendar_sync.png

  11. I logged in to the webmail (OWA) and there Options -> See All Options -> Phone

    Two devices were listed, my old phone and the current. I removed both. I then restarted the phone and the sync seems to be back in order. The phone hasn’t run hot in a couple of hours and both mail and calendar events works fine.

    PS. Before this I had also Reset Network Settings. I have no idea if this was part of the solution. DS.


  12. Nickolaï SALIEVITCH says:

    We still have the problem after migrating some impacted users’ mailbox on Exchange 2010. Note that the ActiveSync flow now use the Exchange CAS component to retrieve the infrmation from the mailboxes

    One difference already pointed out on your previous posts, we have the problem also with Android’s devices.

  13. Hi Robert.

    Good article 🙂
    I have another issue and I just wan’t to hear if you have heard about it before and may have a solution?

    I have a user connected to our Exchange server with two accounts. He currently have an Iphone and two Ipads, IPad Mini and IPad 2. When he upgraded the Iphone to iOS 7 the Exchange accounts automatic changed the sync period to 1 week. But after a couple of weeks it changed back to normal. Then we upgraded his Ipad 2. Same bloody issue! and that is still an issue. Now he upgraded his IPad Mini to iOS 7.1.1, and then it changed the sync period to 1 week on one account and 3 weeks on another account.

    I have tried to delete the accounts, and disconnecting phone/IPad in OWA. But none of that seems to do the trick.

    Any suggestions would be appriciated 🙂

    Best Regards

  14. Debra Lee says:

    I’ve had the same issue since February 2014 on an iPhone 3GS which I gave to my elderly mum. She doesn’t do email or even know how to use internet so it has nothing to do with any of the issues documented here. She doesn’t make calls…it’s just for me to use to call her using my free minutes. I’ve switched it to WiFi only (she doesn’t have internet but I use wifi at my house when she’s here to do any updates) , turned off location services, cellular data off, no internet based apps every possible thing is turned off yet still it was using data pretty much 24/7!!!!! Last year I had a 365 day 350mb data pack on the phone so I could send her photos and skype etc whilst travelling – we never used that amount in the whole twelve months. March 2014 I had to change to a monthly data pack as the 365 day one was no more and since then – every month – it’s been well over the 500mb allowed and they were then taking money from her call credit!! I’ve had to get the carrier to block cellular data their end for now but not happy about this. My 4s does same thing but I have a 1gb monthly allowance so it’s not really an issue for me but still – considering I don’t use email etc on that one either and am on home wifi pretty much 24/7 it’s ridiculous to sed this usage. And turnng off cellular data seems to gave no effect cept when you WANT to use it!! Apple….pfffft!!

  15. Jason Lehr says:

    So annoyed by this issue- I’m a Systems Engineer but there is no good method to really get in there and easily diagnose issues on iPhones- Steve Jobs haunting us from the grave with his control-freak ways! Anyway after struggling with like 100 phone reboots and trying to remove “stuck” accounts by deleting the profile in OWA- finally was able to delete the accounts and re-add by choosing the “Reset Network Settings” option in Settings

  16. Hi Robert,

    I stumbled upon your articles regarding the exchange-sucking-phones-issue, after looking for a solution for my Nexus4-phone for almost a year. Thank you so much for not only finding out about that issue but being so persistent about it. Is there any news on this problem with the updated iOS 8?

    I thought about switching to the iphone after finding out alot of people on the internet having the same problem, but no solution in sight. But if an iphone is no solution, what then? Ditching MSN/exchange/hotmail completely?

    Thanks for your reply!

    A note: I’m not having this issue in a business (exchange) environment, but by only using exchange/hotmail account as a freelancer. The Issue, nevertheless, is excactly the same.

    cheers moritz from germany

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