Exchange Calendar sync loops, drains, and fails

Question

Level 1

0 points

Exchange Calendar sync loops, drains, and fails

It seems I have got the same problem as described here. The symptom is that the Exchange sync never seems to finish. The phone runs hot and probably uses a lot of network traffic. The problem is that the disable/enable of Calendar sync trick fails on my iPhone. It tries for a long time and then it times out. I can't even remove the accounts completely, that fails in the same way.

It's an iPhone 5S running iOS 7.0.5. I'm syncing three calendars. Two Exchange accounts from different servers and one Gmail.

This problem happened to me once before and then I ended up doing a Factory Reset. I'd rather not do that again.

Power assertion timeout: https://dl.dropboxusercontent.com/u/26840/iOS_power_assertion_timeout_DataAccess _Exchange_related.png

and with https://dl.dropboxusercontent.com/u/26840/iOS_power_assertion_timeout_fetchMobil eSynchronously.png

MobileCal: https://dl.dropboxusercontent.com/u/26840/iOS_MobileCal_has_active_assertions_be yond_parmitted_time.png

The preferences timeout:

https://dl.dropboxusercontent.com/u/26840/iOS_preferences_timeout_turning_off_ca lendar_sync.png

I would love to find a solution to this! It could be to the root of the problem, how to force calendar sync off, how to force removal of email accounts, or to something that I've missed.

PS. I've asked the same question here. DS.

iPhone 5s, iOS 7.0.4

Posted on Feb 2, 2014 5:51 AM

Reply

Answer 1

jonelf Author

Level 1

0 points

Feb 3, 2014 2:42 AM in response to jonelf

I've tried Settings, General, Reset, Reset Network Settings to no avail.

Also I'm not the only one with this problem. We are both syncing to the same Microsoft Exchange-version: 14.3.123.0 server.

Reply

Answer 2

jonelf Author

Level 1

0 points

Feb 3, 2014 5:05 AM in response to jonelf

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.

Reply

Answer 3

Mar 13, 2014 7:30 AM in response to jonelf

Not sure if this will help, I found it solved a slightly different problem. the following is a re-post from a different thread.

---

I've had similar issues - although my email and contacts were syncing with Exchange without issue, in iOS7 I developed a one-way problem with calendar sync.

Appointments created on my iPhone were syncing fine to my Exchange server, and were then visible in outlook on my PC.

However items created in Outlook were not syncing to the iPhone.

I'm running iOS 7.1 on an iPhone 5; plus Outlook 10 on a Windows 8.1 machine connecting to Exchange on Small Business Server 2003.

I found a solution here.

On the PC, go to your calendar and right-click the Calendar folder. On the Permissions tab, change the default Permissions from "none" to "Reviewer". Apply changes.

Then on the iPhone, remove and add back the calendar in Settings.

I have 3 separate calendars on my exchange server and had to do this for each one. When I only did it for one calendar at first, this was the only one which appeared on the iPhone. So, it seems to me that this was definitely the culprit.

Interesting that this problem only reared it's head since the iOS7 update. Calendar was working just fine for me in iOS6.

Reply

Answer 4

Sep 13, 2014 10:05 PM in response to A Boy Called Trampoline

I've just started experiencing this on my iPhone 5S running iOS 7.1.2. My phone's battery is drained within 2 hours and the phone is hot to the touch at all times. I'm unable to turn off Calendar syncing within any of the mail accounts on the iPhone, and I'm unable to delete any of the mail accounts either. When I try, I get a translucent "spinner" thing in the middle of my screen that says "Deleting..." or "Turning Off Calendars..." and it basically hangs around forever, never finishes. I have to forcibly kill the Settings app (or sometimes even force reset the phone) to get it to stop.

I've already tried all the suggestions above about changing permissions on Exchange account calendars via Outlook and removing the iPhone as a listed device via OWA, but none of that resolved the issue. I've also tried all of the following:

* Forcibly change all passwords on all mail accounts in iPhone's settings to be invalid, to try to prevent the phone from succeeding at making any connection attempt, and restarted the phone. Didn't help, still couldn't delete mail accounts or disable calendar sync.

* Disable WiFi and cellular data in the iPhone's settings, and restarted the phone. Didn't help, still couldn't delete mail accounts or disable calendar sync.

* Restore my phone from a local backup using iTunes on my PC. Didn't help, still couldn't delete mail accounts or disable calendar sync.

Inspired by the original poster's screenshots, I went into "Settings >> About >> Diagnostics & Usage >> Diagnostics & Usage Data" and found a long list of crash reports all named along the lines of "ExcResource_dataaccessd20...". Every one of these shows process "dataaccessd" being terminated due to a CPU resource usage exception (EXC_RESOURCE, Subtype: CPU, Exception Message: "(Limit 50%) Observed 96% over 180 secs") triggered by thread 0, with the call stacks generally all being down inside DAEAS or DADeamonEAS, both of which (I assume) stand for "Data Access, Exchange Active Sync". So basically there's a bug somewhere in the "dataaccess" component of iOS, specifically in its Exchange Active Sync implementation, that is leading to an infinite loop (pegged CPU and an operation that never completes).

I sure hope someone from the iOS development team is looking at this issue, because it's the single biggest headache I've ever experienced with any Apple product. It has rendered my phone basically useless... I can't even rely on it as simple voice phone because the issue drains the battery so fast!

Reply

Answer 5

Sep 13, 2014 11:34 PM in response to c0d3h4x0r

I finally figured out something that worked, and I think I also know what triggered this issue in the first place.

The fix was to do a "Settings >> General >> Reset >> Reset All Settings". After the phone restarted, I was FINALLY able to delete all my mail accounts and start over by re-adding them one by one.

When I tried to re-add my work Exchange account, it kept refusing to accept my login credentials, which seemed odd. On a hunch, I fired up Outlook on my PC (which has been configured already for ages to connect to my work email) and discovered it was now prompting me for credentials and refusing to accept my login either. I was however able to log into my work email via OWA using the same login, so my credentials are still good... which means that something is messed up this weekend with the Exchange server's authorization. The mail provider my workplace uses is postoffice.net, and the mobile exchange server address is owa.postoffice.net. Anyway, I suspect a server-side problem with authentication on the owa.postoffice.net server is what initially kicked my phone into this awful state.

Reply