No Internet Connectivity on 4G

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Level 1

9 points

No Internet Connectivity on 4G

Hi,

Everytime I turn on the device or switch to airplane mode (ON then OFF), if the device registers directly to 4G network, then I don't have Cellular internet until it moves to 3G. After that it will work on 4G as well.

I thought at the beginning that it's a cellular network issue but after that it seems there is something wrong with my content (backup).

Reset Network Settings didn't help.

Reset All Settings didn't help.

I did restore for the device without bringing my backup -> It Worked !

I did restore and restored my backup (Local backup using iTunes) -> It's not working again!

Sounds like there is something in the device that is causing the above issue to happen.

I'm using iPhone 7 128GB Model A1778 (T-Mobile US Hardware)

I'm currently using iOS 11.1.

This also happened while I was using iOS 11.0.X

I don't know if it happened with iOS 10.X (I wasn't aware yet of the issue)

I don't want to lose my backup because it contains lot of data that I can't delete.

Any idea how can I resolve such a problem?

iPhone 7, iOS 11.1

Posted on Nov 2, 2017 3:53 PM

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Answer 1

Top-ranking reply

tonyhabayeb Author

Level 1

9 points

Nov 3, 2017 12:18 PM in response to tonyhabayeb

I solved the issue.

Here is what happened:

2 months ago I inserted a SIM card of a different carrier that is not formally supported by Apple.

In order to have data connection, I installed a configuration profile with their APN.

Once I got back to my SIM card (official carrier), I removed that configuration profile but it seem that the APN configuration remained in the device although it was removed (I'll explain shortly how I identified that).

The device worked on 3G because my carrier identified other APNs on 3G network and treats it as their formal APN but not for 4G network. That's why when I get my iPhone registered directly to 4G, it doesn't work.

I identified the issue, by opening the iPhone Backup file using 3rd party application that allows me to browse the backup content, then I found the configuration still exists under "System Files/ManagedPreferencesDomain/mobile/com.apple.managedCarrier.plist"

I deleted that file from my backup then I did a "full restore" then "restore from backup" and now everything works perfectly !

It sounds like Apple has a bug in iOS 11 where at certain conditions, the removal of a configuration profile doesn't clean out the system well and causes the trouble and of course none of "Reset Network Settings", "Reset All Settings" or "Reset Settings" under Cellular Data didn't resolve the problem (which I think it's another bug)

Also, before I fixed the issue, I tried to install a configuration profile with custom APN and it was failing becuase the OS identified that there is already configuration profile with APN.

I hope that someone from Apple will ready this out and make sure to place a fix for this issue.

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Answer 2

ChrisJ4203

Level 10

230,678 points

Nov 2, 2017 3:56 PM in response to tonyhabayeb

You need to contact your carrier. They are responsible for the cellular data connection. If you have the phone set for having cellular data turned on and you are seeing a cellular connection and signal, then see what the carrier has to say about their data network. You have done all of the user troubleshooting that you can do for your device. The next step is to contact the carrier.

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Answer 3

tonyhabayeb Author

Level 1

9 points

Nov 2, 2017 3:58 PM in response to ChrisJ4203

I already contacted the engineering team of my cellular network.

They are not seeing a registration signal coming from the device.

And again, in case I do restore without restoring my backup, everything works perfectly.

Once I restore my backup, the problem comes again. Resetting network settings and resetting all settings are not helping as well.

There is something saved in my backup that is avoiding the device to complete registration process over 4G.

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