Windows 10 Mobile build .63 for Insiders may have a data-eating bug tied to Messaging

Early reports are coming in from select users that the latest Insider build for Windows 10 Mobile – build 10586.63 – may have a bug related to Messaging backup that causes excessive cellular data usage.

Starting a few days ago, users have begun to notice that their cellular data pushing towards 1GB in just a few days.

Over at reddit, a few users pinpointed the data leak to Messaging syncing, and history found in Settings. However, neither have been verified by Microsoft at this time although the company is evidently aware of the issue affecting some users.

As a precaution, users can disable Message History & Sync through the following steps:

  1. Settings
  2. System
  3. Messaging
  4. Disable Sync messages between devices

Some early reports we have received suggest that the above will address the problem. The bug does not seem to be an issue with the production build of 10586.29, but only for Insiders. On our Lumia 950 XL with the latest firmware and .63 release we do not see the data drain, but we also did not have Messaging sync enabled to begin with.

To check your data usage:

  1. Settings
  2. Network & Wireless
  3. Data usage
  4. Usage details (below the graph)
  5. Check Messaging and/or System near the bottom, which may be unusually high

At least one report has also noted a higher than usual usage of data by Outlook. However, we do not have many reports to confirm that one.

Bugs on the Insider program are to be expected, and users agree to the risks when enrolling. However, all of this may be moot as we are expecting an update to roll out today that may very well address this unusually high data usage. More on that shortly.

Via: reddit 1, reddit 2 Windows Central Forums

Daniel Rubino

Daniel Rubino is the Editor-in-chief of Windows Central, head reviewer, podcast co-host, and analyst. He has been covering Microsoft since 2007 when this site was called WMExperts (and later Windows Phone Central). His interests include Windows, laptops, next-gen computing, and for some reason, watches. Before all this tech stuff, he worked on a Ph.D. in linguistics, watched people sleep (for medical purposes!), and ran the projectors at movie theaters because it was fun.

  • I just noticed this by accident about 3 days ago.  I did for the purpose of helping my battery life, however.  Ever since turning this off my battery has increased a ton.  Sucks that I have to keep it off because I do want my messges to sync, but hopefully they address this in the next build (or an update).
  • Weird, your battery usage went up with syncing disabled? Many users would advise turning syncing off to save battery life, which makes sense. Odd.
  • He meant that his battery life increased in a good way.
  • Ah, got it! Makes sense.
  • If you have photos sync with one drive, you can easily eat up 2GB+ depending on the amount of pictures you have there.  Although when I check Data Usage: I have System using 5.92GB and One Drive using 2.6GB. 
  • What the guy below said, haha.  Good catch though!
  • my System used 3.95 GB, am i the only one or this is normal, Messaging on the other hand used only 65 MB. sync is enabled.
  • My system is at 12.04GB!!!!!!
  • Data usage for Messaging is 24MB right now, so no problem with the build
  • Is there giong to be a version bump today, anyway?
  • Turning off Skype connection to messaging helped a lot with battery too.
  • Yup, I agree with that
  • How do you turn this off?
  • See my answer to krashek below
  • Thanks!
  • I guess in the messages app. somewhere in the settings. Skype settings to set it on in message app and in skype - settings to make skype the default on.
  • When reach only 3G option
  • I would like to know that too please! :)
  • I posted about this a little while back, should still be the same steps: If you open up the messaging app, use the 3 dots on the lower right corner and go to -> Skype settings. From there there's a button (just text, but acts like a button) that says Sign out. It will prompt you, "Are you sure?" just click Sign out again and Skype will now be disabled within the Messaging + Skype app (note it takes about half a minute before it actually signs you out, just wait until the screen changes before doing anything else).
  • Funny, I think this bug only appears if I let some sms sitting there without read them ( spam sms)
  • This is me hard last week when I was travelling for work. Battery was nearly sucked dry in 1/2 day and it blew through over a 1gb of data.
  • 1520.... No problems with excessive data usage whilst syncing. On the other hand Edge and Reading List do not sync at all anymore since .63, come to think of it!
  • My System usage says 865.51 MB. But I believe it also counts the data used during OS upgradation.
  • It counts Store app downloads
  • It counts fapping
  • Mine it's around 5.5GB
  • Same posted in the forums about this the other day. But the update was over wifi, so I'm at a loss....
  • I wonder if this leak is contributing to the fact that when my mobile data is on my battery drains 40% just sitting in my pocket doing nothing for an hour and a half, but when I turn my data off my battery doesn't drain at all. I'm running .63 insider on a L925.
  • I'm not too sure but it might be because when your mobile data is on, your mobile carries out syncing which drains battery
  • Only 70mb from 2 GB used.
  • It's good to have unlimited data plan ;)
  • But still, if this bug exist in ur device for example, ur battery will probably drain faster like other user dude :/
  • Or a reliable phone operation system..depends
  • Part of the reason I switched to a BlackBerry PassPort SE. It was quite a shock at how fluid it is compared to Windows 10 Mobile. Still plan to come back once the Surface phone is released, though.
  • Made me chuckle
  • You're the first one I heard who moved from Windows to BB.
  • Hmm, I have Sync messages between devices on for my Lumia Icon and I'm not seeing and data eating issue.  The only difference with my setting and the screenshot above is that I have Allow MMS if cellular data is off turned off.  Lastly I don't recevie a ton of text messages so that could also be why I'm not seeing the issue either.
  • Then again, not expecting MS to release new Insider build W10M soon :/
  • ...Coming Soon...
  • We are in 2016 and Windows mobile still not ready, hope it will be soon
  • Why not use the word hopeless
  • Really this is not at all acceptable..
  • It's only the insider build, right? If so, then its perfectly acceptable.
  • You say it isn't acceptable. I don't understand that thinking. This download is an insider build. It's a beta test for all intents. It isn't like your carrier pushed out this update. You elected to use it, knowing full well there may be issues, then you're upset because there are issues?
  • It is not acceptable that it isn't ready. We are now nearing a decade into the mobile revolution and Micrsoft still doesn't have a complete platform. Will W10 be it? Who knows!? Posted via the Windows Central App for Android
  • Yeah, noticing System is 7.4 GB
  • Here we go. Time to start unraveling.
  • Only data bug I've noticed is that it doesn't count data used when my 950XL is set as a hotspot. Which is really annoying...
  • Tell me about it! 90% of my monthly data usage is from the hotspot. That's something I need fixed.
  • Wow! My system usage says 6.1 GB! Thanks for the info. Turning the sync off to see if there are results in both battery life and data usage.
  • Dam it, today I noticed that.. 760mb spent on system..
  • just checked and its 2.12 GB for Messaging on 950 (non-insider). Ridiculous.
  • System used about 5.6GB on my non-insider 950XL over the last 30 days (half Wi-Fi, half cell), I moved my SIM back to my 830 until they get it fixed.
  • I can confirm that disabling this setting on my 950XL running the always-production OS has stopped the excess data usage of System.
  • Can you change the title to "data PLAN-eating bug?" You sacred the #$%& out of me there when I thought maybe I permanent lost data.
  • Don't worry there are no pellets contained within :P.
  • Daniel - pretty sure this bug is not limited to insider preview.  This past billing cycle I had the same symptoms of high system data usage only on mobile, and it chewed through 90% of my data plan, and was also draining my battery very quickly.  Will be paying hefty data overages this month :( After turning off message sync between devices, the system data immediately stopped increasing, while battery life significantly improved.  I'm on 950 XL (dual sim), production build 10586.29
  • I would agree with that. I actually noticed this when I was on build 10586.29 on my 1020 (and even posted some solutions and what I had tracked down in the forums), but the issue had been present even before then. Now it appears it's affecting more phones/people.
  • Did you really pay hefty data overages? Or are you just stirring the pot? For some reason I doubt people are actually paying tons of money for overages. You get warnings from your carrier first. That prompts a quick investigation on the users end to figure out the problem ASAP. Theoretical scenario to scare Microsoft into a fix?
  • Between this and the flat-out broken 802.11ac / 5GHz wifi support for me on my 950XL, this is killing my bill for January (went over my 4GB of data three times now).  Really hope both issues are fixed by the next update. My system data is at 16GB, but luckily, ~10GB of this was on Wifi.
  • Messaging App is top battery hog on my L928, am disabling sync as of now. I am not affected by high data usage though. BTW, I am not using the Skype feature.
  • Even Joe Belfore avoids Windows Phone on his vacations because they're full of bugs. That's sad. Tho i am a windows phone user but its very late.
  • Also Satya Nadella
  • He uses the competition devices to learn them.. learn how they could improve Windows Phone.. and to learn how their apps are on the competition devices.. 
  • I must say they have learned a lot from iOS ,their knowledge have shown results like wp has 3% smartphone market share in the whole world...
  • And for the first time ever, Windows Phone is a feature rich Mobile OS.  It has all the necessary features built in, unlike WP7, WP8, and WP8.1.  So yeah, I'd say they've leaned a lot. Market share isn't everything. 
  • Oh you ate that bull right up didn't ya
  • Lmao
  • Lol even majornelson does though I dont think he broadcasts it to the world that often anymore
  • Had massive unknown data usage in december and even bought extra traffic for the holidays, but it was gone in no time :( hopefully they fixed this in the next build
  • I have both latest build and firmware on L950 with sync enabled and I don't have any issues with data eating bugs.
  • meanwhile my System & Reserve storage keeps increasing everyday, without apparently installing any updates or downloading anything.
  • I was waiting for confirmation from the fiance before I responded to your tweet, but she's on .29 and it too has the bug.
  • It doesn't. I am on .29 on my 950XL and System has only 9MB of use.
  • It actually does, but it's not affecting everyone. It appears that it's getting more widespread now. If you don't have the issue then that's great, but it doesn't mean that it's not happening or that there isn't a bug. I posted about this issue several times including my solutions and what I had tracked down, long before this article ever showed up.
  • Keep developing stupid keyboards and apps for iOS and Android while your new mobile platform keep languishing with this bug fest and poor feature parity even compared to Windows Phone 8.1.
  • You haven't a clue about how software development is done, do you? Then I saw the name of the person posting. Nope, you don't have a clue.
  • I wonder if the mote devices it has to sync, the more battery and data it uses...i have skype on 3 other devices always on...
  • My phone jumped from 2-4gb in 2 days. Ouch!
  • Oh Microsoft
  • I've blown through 3GB in my last cycle, and all of it seems to be related to Outlook, or untrackable - I've turned data off for the mean time.
  • I'm not sure about data drain, BUT I did have an issue with messages syncing from 1-2 years ago. Even after i deleted the messages they would automatically down load again. One would think that deleting them from my phone would remove them from whatever server stores them but that doesn't seem to be the case.
  • Well, now we know why Joe Belfiore is using an iPhone instead of Windows Phone.
  • Except that is not what he said he was doing. Thanks for trolling, however.
  • I was joking. Calm down.
  • How was that a joke?
  • Jokes are supposed to be funny.
  • That would explain it, I lost 750 Mb in no time at all in two days, never had this before
  • System is 10GB, but Messaging is <100MB.
    Most of that 10GB was on WiFi, so I'm not too concerned.
    This is a Lumia Icon with .63.
  • I have the setting turned off from the beginning I upgraded to the 10586 builds. No data drains and msg still synced fine with my messaging app on my laptop and tablet, even skpy desktop app syncs but just longer sync time.
  • Btw. Is there any possibility to sync not only messages history between devices but call history too?
  • I don't have this feature turned on anymore because it restores junk without proper names. I use the contacts + message backup application to backup my messages...
  • Thankfully my messaging app is showing only 0.84 Mb used. 950xl India.
  • I'm seeing this problem on the .29 build...I really think this is a problem on the back end.  I restored an old 640 to 8.1 and it didnt restore the text messages properly either.  Not using data, but had many incomplete conversations restored etc.
  • I've noticed this too in the last week or so. Sometimes the background tasks get so out of hand that my phone doesn't charge or loses charge while plugged in. Then everything goes back to normal if I turn on airplane mode.
  • I burned through 5.5 gb of data in 14 days, at which point my cell phone provider shut off my data because my monthly bill (3gb,65$) was being exceeded by $50. Looks like I'll be having a hefty phone bill at the end of this month and nothing I can do about it....
  • You could send a thank you message to S. Nadella.
  • Just checked and not seeing anything here with L950 on .63. I have only used 355.8MB of total data with 11 days to go before my 4GB reset. Messaging 3.06mb & system 5.69mb Cheers
  • The best thing about having a windows phone use to be how smooth and fast the OS was. That's a thing of the past now.
  • I dont have the insider build - have production build 29 on my 950XL. When i saw this on twitter earlier, i checked my data usage and noticed that i dont have ANY usage on cellular! It shows 100% of my usage as wifi... when thats clearly not correct as i spend my work days at work on cellular... I wonder if its getting confused with my naming the SIM1 as AT&T? It shows AT&T = 0, WIFI = whatever usage i have had and SIM 2 = 0 No mention of SIM 1 so it knows i renamed it but usage is not correct at all... I see system as one of the major users of data, but then again, when i looked back at my cell usage from ATT records (online account), i see no appreciable difference from pre-950XL use and now...
  • It does the same for me shows all my data as Wi-Fi usage. It's just another bug in 10.
  • Thanks for information
    Lost 2GB in 15days 640XL .63
  • Only used 107mb, 3gb on wifi the last 8 days - Lumia 1020 on .63 so no issue here.
  • The whole OS not ready. Microsoft isn't employing more ppl on windows 10 mobile and the fixes are just minor bugs.
  • Insider program is pre-release software ergo, bugs. We cannot confirm that this issue exists on .29 aka production release.
  • Yeah I've been getting excessive data usage
  • I think this is the isse I've been having in the .29 production release on my 950. System ate up neay 2 GB data in the first 5 days usage on my data plan billing period.
  • Strange, just checked mine, 930 on .63, and only 250mb since last weds, which is about average for me.
  • Does anyone else have a 'device is charging too slow' prob even if connected with the stock cable??..#lumia830
  • 950XL   .63    No messaging related data leak to report. <100mb in last 30 days. Actually surprised it is that low. Texting is my connection to the world.  
  • As far as 950XL devices running the current public version of Win 10, my phone has shown no issues with excessive data and I do have msg sync enabled. It sounds like there may be some combo of other apps running or specific settings in use resulting in the issue.
  • Try to leave 1 or 2 unread sms on your phone.. Wait a few days a check how it's going :D
  • I also notices on my 930 with the exact version that i pushed 2GB in just 2 and half weeks although cellucar counter says that i have 1GB more and the counter doesnt show messager to take a lot of them.
  • Not getting message notifications, anyone with a solution
  • I have the same problem but it's not permanent. Sometine notification work, sometine not...
  • Mines at 14mb....could it be that those who report high usage are heavy messagers with multimedia?
  • Data sens on windows 10 mobile is very buggy too ...
  • that's what sucks about insider program. people get bugs but then complain about them. W10M is cool but fast ring and even slow ring is always a risk.
  • 1.5 GB in 10 days. Guess I'm paying extra this month. :( The best part is I removed myself from Insider yet still got the build. Even the app said I was not registered as an Insider. To get back on the production ring, I had to sign up as an Insider again then remove myself from the program.
  • 1GB in two days friend. :(
  • Thank you for posting this. Hulkulesenstein is my reddit username, the mods did not find the need to sticky the post despite multiple users per day posting questions and concerns. The fix is an easy one and as noted in one of the post comments the data team at Microsoft is aware of the issue. Unfortunately it cost many users, including myself, lots of money in overage fees as I do not have an unlimited plan. Also as an fyi, this has been around for at least two builds. It is not exclusive to .63
  • 2gb data usage in system!!!
  • I have never used more than 3 GBs in a month, this month I used almost 7 GBs. I didn't notice the data as much as the battery, it would be dead in four hours. I turned of message sync 3 hours ago and have lost only 6% of the battery. Thank you for posting this!
  • Reminds me of that nasty bug wp had with yahoo pop3
  • Over 4GB for the system. Cost me $15. The data sense app should have capped it, or warned me at the 3GB mark, but apparently that feature isn't working, or doesn't apply to the "System". I'm down with dealing with bugs in a beta software, but costing me dollars is a little farther than I'm willing to go.
  • I have the same problem with my 930 my data plan is 2gb per month and my carrier warned me one week ago that I have 10mb which according to data sense it's wrong.
  • My phone's measurement is correct, and lines up with the carrier's, but Data Sense simply didn't notify me or do anything. I was trying to find the data hemmoraging last month, but the data usage is listed in descending order of use. Except "System" which is always at the bottom of the list regardless of data used. That seems like a poor choice to me, as I didn't even think to scroll all the way down to check it until I saw this.
  • This has also been dicussed here in our forums. Hopefully a fix soon.
  • Did you read my question on our forum??? I believe so.
  • Hey Bug, why eating my data, eat something else. Airtel plans are costly.
  • Yup this cost me $50 in overage charges last billing cycle. I couldn't figure out why every other day I was blowing thru another Gb, even when I had background data turned off and was super careful about data. Oh well! Happy to know how to work around it.
  • I'm only running the .29 revision of the OS on my Lumia 950 XL, but was forced to shut off cellular data before it could blow through my entire data limit this month. All possible options related to "only download when on Wi-Fi" are turned on, and the phone had had plenty of time on a Wi-Fi connection to have synced down everything when I initially set it up. But within the first few days of this billing period, the System app chewed through over 1.6GB of data on my cellular connection, and has subsequently gone through over 1.8GB on Wi-Fi. Messaging, Outlook, and so forth only show reasonable amount of data use, and I don't stream video/music or anything. An update to the Messaging app was released after I had to shut off cellular data, but I haven't been game to try turning it back on to see whether it made any difference.
  • Hope they will fix this soon enough...
  • I have problem on my Lumia 930 Insider program 10.0.10586.36. First I noticed that in late december and now a few days this month (from 24th...). I belive this was data we sent to Microsoft. System file is on top with 1,17GB in last 30 days. My data plan is big enough but my battery life is what drives me crazy. It drains out in 6 hours!!! I must charge my battery two or three times a day in this time. 
  • Have any of you calculated how many SMS and MMS you need to synchronize before you reach 1GB of data? I highly doubt that SMS backup is the biggest issue her. As a reminder: the maximum file size of one single SMS is less than one KB.
  • This is kinda weird that MS want us to move from good old windows 8.1/7 to an totally unfinished product called windows 10? #notfare
  • OMG thank you! This issue has been going on for weeks.  I've called AT&T multiple times because my data was being consumed by system but I don't use much data.  Maybe 2 - 3 GB per month.   30 day period SYSTEM has consumed 4.15 GB.  **** you Microsoft your hands are in my pocket when you pull **** like this.
  • strange with this update all my whats app contacts have vanished. did a soft reset , reinstalled the app and even did a hard reset . any workaround ?
  • Anyone know if 10586.7 addressed this problem? I'm afraid to turn message syncing back on and find out/