iPhone suddenly drains battery due to constant push polling
Posted by Dan Israel on Nov 6, 2009 in Information & Technology
One of our users suddenly began experiencing a severe draining on his iPhone battery. There are variety responses to this topic, the least of which was to change the iPhones mail retrevial from Push to Fetch. Howver, other iPhone users were not experienceing this issue. So we set out to troubleshoot what was happening. After two days of research, below is our results and the resolutin that worked for us.
Constant polling in Push modeThe first thing we detirmined was that the phone was constantly polling the exchange OMA (Outlook Mobile Access) website of the exchange server. This was both visible and audible if you are near a set of computer spearker that can pick up the iPhones RF. Switching the ActiveSync mode to Fetch, did indeed resolve the battery issue, but it simply masks the problem. If you are an Exchange Administrator or have a good relationship with one, you can verify this is an issue by checking the Excahnge OMA website logs in iis. These are difficult to read, but for a medium sized business, you’ll see a noticable increase in the traffic to that website, as the iPhone polls iis constantly. This might also be noticalbe in Firewall https logs.
ResolutionWe found the problem to be caused by a corrupt “Meeting Request” in the users mailbox. The phone was not able to open this and process automatically, thus causing an error and the ActiveSync polling to restart. No other functionality seemed to be impared, only that ActiveSync push would constantly fire, due to an inability to sync all mail items.1) To eliminate it, we sorted the Users Inbox by Type in outlook.
2) We then deleted all the meeting or calendar mail requests.3) Empty the deleted items as well to completely remove the corrupt invititation.4) Deleted the iPhones Exchange Account, recreated it, and let the mail sync up.Once you delete the account, you can recreate it using the AT&T infomration below. No data will be lost, as this is simply a syncronized copy of the exchange server.
AT&T Support On-Line
2) We then deleted all the meeting or calendar mail requests.3) Empty the deleted items as well to completely remove the corrupt invititation.4) Deleted the iPhones Exchange Account, recreated it, and let the mail sync up.Once you delete the account, you can recreate it using the AT&T infomration below. No data will be lost, as this is simply a syncronized copy of the exchange server.AT&T Support On-Line
Thanks a bunch, had a user with this issue and was about to rebuild his mailbox. This saved me some time!
I was wondering if you could explain your process denoted by the link to AT&T. As that link is no longer valid.
Thanks
Mike,
Looks like AT&T moved this link. I’ve updated the link above and here it is again for reference.
http://www.wireless.att.com/support/tutorials.do?tutorialsCategory=E-mail&tutorialId=851390&deviceId=11990
I’ve run into this a few times. I suspected it had something to do with a meeting request but I’m not versed enough in IIS logs to sift through the massively inflated logs and figure out exactly what item caused the ActiveSync jam. Thanks for your insight here.
Have you attempted to reproduce the problem to figure out under what circumstances the meeting request fails to sync?
Jim,
As far as I can tell, this is corruption that occurs through a non-repeatable parameter. It may have to do with traveling – as the individuals it has affected most, always seems to have sync issues when they return to the office. But nothing I’ve pinned down yet…
Hi experts,
My problem is somewhat strange..!!!
I configure exchange mail, sync my emails, calendars, and then completely switch off ALL radios, like 3G, WiFi, and services like location services, push etc but it still drains the battery (100% to 20% in less that 2 hours) and becomes very hot even if i don’t use it.
Not only that, when this problem starts, I can’t even delete any of my SMSs if I want to; the delete option just flashes 🙂 🙂
Any idea what could be the problem; i apprciate if someone can help.
Cheers,
Aamir
PS: If i remove the exchange account, my phone becomes normal.
Aamir…
If you hadn’t put that PS, I would have said you have an iPhone problem. But given removing the Exchange account removes the problem…this has to be a corruption in the Exchange Data. My advice would be to load the Exchange data 1/3 at a time. Try Mail only. Then try contacts. Then enable calendar. Also, under settings only snyc the smallest amount.
My guess is the phone is trying to process something internally…like a calendar event or reminder that is corrupt. Otherwise, putting the iPhone into Airplane Mode would not drain the battery.
And just to be clear… does the screen shut off or does it stay on continuously when the Exchange account is enabled.
If that doesn’t point you in the right direction…create a dummy account in exchange (or talk to your Exchange Admin) and sync to it. See if it exhibits the same behavior.
Hi Danisrael,
Thanks for your reply and suggestions.
The screen during this issue works fine but response is a bit slower than usual; in addition to battery draining the only unusal events i observe are:
1. I can’t delete any SMS; the “delete” option goes off in a flash.
2. iPhone becomes hot even if i don’t use it.
I will try your suggestions and keep you posted.
Thanks again,
Aamir
Hi Dan,
BTW, earlier when i didn’t R&D on this issue myself, Apple replaced my iPhone 5 times in 4 months becuase i eventually used to restore it from the previous backup 🙂 :).
Later i came up with this idea of making changes slowly; i mean adding stuff one by one and keep a record of them.
That was just FYI, how generous they were on replacements 🙂
Regards,
Aamir
Great site. I am veiwing it on my iphone and it looks good. Some very interesting comments. Keep up the great posts.
Thanks for the posts.
Reachieved my new iPhone 4s last week and used a previous backup to set everything up.
Immediately noticed that the battery level was decreasing at an alarming rate (dead after just 5 hrs). Also noticed that some calendar notifications would flicker, like it was being updated repeatedly.
Went to the Genius Bar in hopes that could determine what process was out of control. They were of little help, giving me a replacement iPhone to try and also suggesting I not restore from backup but instead set everything up manually. Tried this, setting up only my Outlook Exchange and loading a handful of apps. Still had the problem.
Because of the flickering notification event, next disable calendar and reminder sync, only getting mail from Exchange. Battery life returned to normal. So searched web for Exchange and battery problems and found this site.
So went to Outlook, deleted calendar related emails and events from both Inbox and Calendar, especially repeating calendar events.
Turned on calendar and reminder sync again and problem with battery life and the flickering notification events are gone.
Life saving post! I was at wits end with both my iPhone and iPad and this saved the day. I am sure it will come up for others on our servers, so it is great to have this solution in hand. Thanks!