Database Users

Unable to make calls while connected to 4G(LTE)

Hi guys,
I've been a visitor of the forums over many years now. Learned quite a bit reading all these great posts.
I'm constantly changing phones but always return to Samsung. Now I'm moving from the Note 5 to the S7E.
I just picked up the S7E today and I'm very impressed. Phone looks great and is very fast. A couple of hours playing with the phone I noticed a big problem. I'm unable to make calls when my phone is connected to LTE. When I attempt to call someone it doesn't drop to 3G to place the call. Also my Internet stops working. I can't force 3G/2G and my only option is to reboot the phone. Once I reboot, I'm able to force 3G/2G and I'm able to make calls and Internet works before and after calls. But in this mode I'm stuck without LTE.
Do you think this is faulty hardware? Or should a software update fix this?
Many thanks to XDA community!

Who is your carrier and which exact variant (SM-G935T, ...935V, etc.) of the device do you have?
Are you in the U.S. or somewhere else?
If this is a carrier-specific device being used on its intended carrier's network, then this problem is something their support people could (and should) be able to help you with.
There aren't enough specifics in your post for anyone to have a reasonable shot at helping with this issue.
Also, I just noticed you posted in the general discussion forum. This post is really asking for help and would be a better fit for the Q&A forum.
Sent from my SM-G935V using Tapatalk

Hi,
I bought the international version (SM-G935F). It does not have any carrier branding.
I bought it in Switzerland and I'm using it in Switzerland with a Swiss carrier.
Mods, please move this thread to the appropriate section if it doesn't belong here.
Thanks!

afurtado said:
Hi,
I bought the international version (SM-G935F). It does not have any carrier branding.
I bought it in Switzerland and I'm using it in Switzerland with a Swiss carrier.
Mods, please move this thread to the appropriate section if it doesn't belong here.
Thanks!
Click to expand...
Click to collapse
I also had an S7 Edge with calling issues (dropped every call after a few seconds, possibly trying to switch from 4G to 3G or from 3G to 2G). It turns out it was defective and the replacement works as intended.

Just did a hard reset now.
Was able to make one call. When I tried a second time, same issue. Reboot seems to allow me to make an initial call but then same issue again.
Will take it back tomorrow and hope they have a replacement in stock.

The Feature you are talking about is Voice over LTE! Here in germany this is only anabled in the branded Provider Firmwares like from Vodafone or t-mobile germany. If you have an unbranded Device like i have G635F than VOLTE is not working cause its locked! Not Sure how this works with swiss Providers. In germany VOLTE only is working with Company branded Firmware! And to be honest i am rally worried about that cause i will never use branding Firmwares.

Update: took the s7 edge back to the store and of course the phone worked perfectly. There was nothing they could do as the phone worked fine and we were able to make many test calls.
Phone worked fine during the day but when I got home the problem started again. After some testing, it seems the problem only occurs when connected to 4G+/LTE+/carrier aggregation.
Couldn't place any calls at home this morning but at work where I only get 4G everything works perfectly. Very strange.
In Switzerland I don't think we have VoLTE. When we place calls the phone drops to 3G but for some reason it's not happening when connected to 4G+.
Ill do some more testing today to see if I can find any 4G+ areas near work to test.
Sent from my SM-G935F using XDA Free mobile app

Same issue
Hi,
I just got my new S7 Edge (SM-935F) and I think I have the exact same problem. When I'm in the city where I live (Morges, Switzerland), I can't make or receive any call while on 4G but data works. Switching to 2G allows me to make or receive call though.
Then, when in a different city (50km away), everything works as it should be (call and data on 4G). Did a factory reset and it also didn't change a thing.
The guy from my carrier's shop (Sunrise) told me that there was a known issue with 4G calls on the S7 and S7 Edge in different cities (mostly in the canton Valais). I've also been told that Samsung is working on an update to fix it so returning the phone to get a new one would be useless. Did he tell when that would probably be fixed ? Of course not..
I hope someone find a fix soon
Looks like the antenna gate from the iphone 4 but seriously how can something like that still happen

Hi,
Looks like we have exactly the same problem. I work in Geneva but live in Gland. Today I tested my phone in Geneva and it worked perfectly everywhere while in 4G or 4G+. As soon as I arrived home in Gland I'm unable to make calls so I have to force 3G/2G in order to receive and make calls.
By the way I also have sunrise as a carrier.
Good to know that it's a known problem and that they are working on a fix. It's very annoying... Hope they fix it soon!
Sent from my SM-G935F using XDA Free mobile app

Same here,there is any fix?. Thanks

Unlocked S7 from Sprint and failed attempts to get on T-Mobile data

I was finally able to get Sprint to unlock my S7 and my husband's S7 Edge. I then had to run the 'Unlock UICC' but I was still unable to get on the T-Mobile data network. It turns out T-Mobile did not activate the data component on our accounts. After adding the APN, updating their system and two hours later, the S7 Edge connected but my S7 remains unable to connect. T-Mobile couldn't figure it out and I have a ticket open with a 72 hour window. . .
Two questions:
1) I think the error has to do with the fact that with the latest Android update, I did it after my phones were unlocked by Sprint and the T-Mobile SIM card was recognized by my S7. The reason is because this is the only difference from the S7 Edge and I keep receiving error messages about the update not being confirmed. It also keeps attempting to run the PRL update process and I don't think that applies to the T-Mobile network. Is a factory reset the only answer?
2) If I factory reset my S7, will that take away the Sprint intro and bloatware when I restart it with my T-Mobile SIM in the phone?
Thank you in advance for entertaining my newbie questions.

wontonie said:
I was finally able to get Sprint to unlock my S7 and my husband's S7 Edge. I then had to run the 'Unlock UICC' but I was still unable to get on the T-Mobile data network. It turns out T-Mobile did not activate the data component on our accounts. After adding the APN, updating their system and two hours later, the S7 Edge connected but my S7 remains unable to connect. T-Mobile couldn't figure it out and I have a ticket open with a 72 hour window. . .
Two questions:
1) I think the error has to do with the fact that with the latest Android update, I did it after my phones were unlocked by Sprint and the T-Mobile SIM card was recognized by my S7. The reason is because this is the only difference from the S7 Edge and I keep receiving error messages about the update not being confirmed. It also keeps attempting to run the PRL update process and I don't think that applies to the T-Mobile network. Is a factory reset the only answer?
2) If I factory reset my S7, will that take away the Sprint intro and bloatware when I restart it with my T-Mobile SIM in the phone?
Thank you in advance for entertaining my newbie questions.
Click to expand...
Click to collapse
You may have to flash tmobile or the u firmware because even though the hardware supports all the bands, the software doesn't.
Sent from my SM-G930U using XDA-Developers Legacy app

Thanks Ivpre! I'll try that and see where I get. I appreciate the help.

wontonie said:
Thanks Ivpre! I'll try that and see where I get. I appreciate the help.
Click to expand...
Click to collapse
Just remember, if you put a sprint sim card back in, it will probably relock the phone and you will have to unlock it again.

As long as it was unlocked properly it shouldn't lock not matter what sim you use , and if you put the U firmware on it you can freely switch between all carriers with no issue at all

goonygugle said:
As long as it was unlocked properly it shouldn't lock not matter what sim you use , and if you put the U firmware on it you can freely switch between all carriers with no issue at all
Click to expand...
Click to collapse
True, but some online services for this are hit and miss.
Sent from my SM-G930U using XDA-Developers Legacy app

lvpre said:
True, but some online services for this are hit and miss.
Sent from my SM-G930U using XDA-Developers Legacy app
Click to expand...
Click to collapse
Yeah that is what I'm finding out, I have done a few unlocks over the last few days for people who lost their unlocks, I have yet to have one of mine re-lock, but certainly doesn't mean it won't happen

Verizon S8 with tmobile SIM - Cannot run system update

Neither on wifi nor cellular will it check for update. I get the error "sorry, we are having trouble authenticating your device"
Any idea how to fix this ?

wondering the same :/ anyone have anything?

see my post here. besides flashing the t-mobile ummm rom I guess over it, you won't be able to update. I've tried samsung and t-mobile and the only thing that will work besides that is to borrow a sim from a friend and use that... https://forum.xda-developers.com/galaxy-s8/help/best-buy-screw-t3594359/page2

try it today. it should work. the servers were having issues last night and this morning.

lotreaglesfan said:
try it today. it should work. the servers were having issues last night and this morning.
Click to expand...
Click to collapse
will not work because system updates are coming from carrier and having a tmobile sim in a verizon phone means verizon will not allow you to connect to their update server...

insomnia said:
will not work because system updates are coming from carrier and having a tmobile sim in a verizon phone means verizon will not allow you to connect to their update server...
Click to expand...
Click to collapse
Thats not the case. I am using vzw GS8 on att and I receive updates fine

Well I'm confused then. I was able to do the last update with a t-mobile Sim in the phone? Right now when I try checking for updates it errors out saying it couldn't be authenticated. Anyone have any clue?

Hope I can help you!
How to update your system if you're not using the carrier from your S8(+) version.

insomnia said:
Neither on wifi nor cellular will it check for update. I get the error "sorry, we are having trouble authenticating your device"
Any idea how to fix this ?
Click to expand...
Click to collapse
you wont be able to updated through wifi or LTE unless you use a verizon SIM but you can do it easily using your computer and samsung smart switch.

eoga said:
you wont be able to updated through wifi or LTE unless you use a verizon SIM but you can do it easily using your computer and samsung smart switch.
Click to expand...
Click to collapse
Are you able to update using your computer?

insomnia said:
Neither on wifi nor cellular will it check for update. I get the error "sorry, we are having trouble authenticating your device"
Any idea how to fix this ?
Click to expand...
Click to collapse
Try to get at least an inactivated Verizon sim card from any Verizon store or you can also try a normal working Verizon sim. I had AT&T Galaxy S5 and it needed the carrier's sim card to even check for update. I took the sim, put it in, checked for update and was able to install it.

Fix to your issue
Hey guys so I do also share the same situation, I have a Verizon s8+ yet I have T-Mobile One as my coverage
Because it's not authenticated as a Verizon provided account it simply won't update
Now.. the solution to updating isn't directly on your device.
It's within the Samsung Smart switch App for either Mac or windows, you can run an update through there with little to no problems at all and finally keep your device up to date without having to return it for an unlocked one.
Just a brief note regarding the smart switch App, keep in mind that sometimes the update will freeze at a certain percentage on the computer so just be sure to close the app out only if your Samsung device hasn't received the green upload screen yet.
Hopefully this helps out alot of you guys ?
Best regards

lotreaglesfan said:
see my post here. besides flashing the t-mobile ummm rom I guess over it, you won't be able to update. I've tried samsung and t-mobile and the only thing that will work besides that is to borrow a sim from a friend and use that... https://forum.xda-developers.com/galaxy-s8/help/best-buy-screw-t3594359/page2
Click to expand...
Click to collapse
I'd like to flash mine to t mobile, I'm begging you to help me with this!!!
Sent from my SM-G955U using Tapatalk

I've seen a bunch of info on the forums on how to flash the T-Mo ROM on an s8 - as well as flashing the Samsung Unlocked ROM on the s8 but frankly, almost all the threads are from back at the phone launch - and it is unclear to me which roms & programs to search for.
In a similar vein - I'm a noob to the whole process using oden - which I think is what i would need to use. I have experience from years ago running cyanogen mods on a nook tablet and messing with windows phones - but nothing recent and things have changed a lot.
I've read conflicting reports throughout the forums on doing this...
I'm running a VZW Branded (but it's now "unlocked")
Model: s8 SM-G-950U
Build #: NRD90M.G950USQS2BQL1
Baseband #: G950USQS2BQL1
What I'm looking for (really the right word is "NEED"):
Access to lower 700 A block (full band 12 use)
Ability to get OTA Updates
Mobile Hotspot Functionality
WiFi Calling
VoLTE
Bixby
If I could have these all running the Samsung Unlocked ROM - then that would be preferred...
If not - I would want to flash the T-Mobile ROM.
I need to know ASAP as I only have 14days from today (2/14/18) to figure this out or go back to VZW
Many thanks!
~chris

Urgent : Unlocked at&t s7 No Signal at all; sim slot/antennae fine

Hi guys,
Been into android modification since 7 years but gave up since my last 2 phones. So i got this unlocked at&t galaxy s7 in uae and it worked like charm, the network and coverage. I then started usingthe phone in pakistan too and it worked well even here. So one day i connected to gear vr so that i can initiate the oculus data installation as first time setup but the gear vr kept on disconnecting automatically. I have used it before too but never had problem. Then i rebooted the phone and i find that i have no signals at all even though my sim contacts are being displayed and there is no “no sim” message on statusbar even. But dont have any signals at all. I then inserted my sim to iphone and it was working perfect. Then i inserted different carriers sims to s7 but yet they werent working even. I then cleared the cache, factory reset, cleaned the sim slot and the sim , but no success. I left ky ohone turned off for days andeven drained battery 100% many times to calibrate and perform hardware reset but no success. I then sent the phone back to uae for repairing from my friend as i thought that the antennae were the one’s responsible but before he even thought of disassembling the ohone, he inserted uae sim and it worked perfectly. Call and data were working perfectly. Any idea what is the problem? Kindly let me know pleaseeee. Is there any problem with frequency? Like gsm or cdma? But the phone worked before. I tried to enter the settings of manually selecting networks but there was error popup “No service and signal”. Signal strength 0asu -113dvm

Loki_GOM said:
Hi guys,
Been into android modification since 7 years but gave up since my last 2 phones. So i got this unlocked at&t galaxy s7 in uae and it worked like charm, the network and coverage. I then started usingthe phone in pakistan too and it worked well even here. So one day i connected to gear vr so that i can initiate the oculus data installation as first time setup but the gear vr kept on disconnecting automatically. I have used it before too but never had problem. Then i rebooted the phone and i find that i have no signals at all even though my sim contacts are being displayed and there is no “no sim” message on statusbar even. But dont have any signals at all. I then inserted my sim to iphone and it was working perfect. Then i inserted different carriers sims to s7 but yet they werent working even. I then cleared the cache, factory reset, cleaned the sim slot and the sim , but no success. I left ky ohone turned off for days andeven drained battery 100% many times to calibrate and perform hardware reset but no success. I then sent the phone back to uae for repairing from my friend as i thought that the antennae were the one’s responsible but before he even thought of disassembling the ohone, he inserted uae sim and it worked perfectly. Call and data were working perfectly. Any idea what is the problem? Kindly let me know pleaseeee. Is there any problem with frequency? Like gsm or cdma? But the phone worked before. I tried to enter the settings of manually selecting networks but there was error popup “No service and signal”. Signal strength 0asu -113dvm
Click to expand...
Click to collapse
Forgot to tell, my phone has never been rooted, i even tried to enable/disable “Enable hd LTE features” but no luck. Its on 7.0. Dont recieve OTA. Not blacklisted either. Pakistan doesnt have CDMA. I have even noticed it recieving weak signals compared to my iphone when the phone was working ok. And my radio is showing to be off and when i turn it on from the dial code menu. It doesnt keep turned on and it turns off automatically. I still have the imei amd baseband version. Dunno what the issue is.

Kindly reply guys
Please help

Loki_GOM said:
Please help
Click to expand...
Click to collapse
Settings>connections>mobile networks> apn settings or access point names
Manually enter your carriers information you'll have to ask them or look it up online sure its easy to find they might even help you in store
Its not good for you to buy these US phones outside of the US because changing CSC to INS/INU/PAK could prove to be difficult being it was never supported by snapdragon G930A model but only exynos G930F although it's not impossible
/system/csc/others.xml is where your answers are waiting for you unless you update to oreo then it'll be in /system/omc/cscfeature.xml and cscfeature_network.xml
You will need a root file manger to be able to see what I'm talking about then you will have to figure out what those "strings" mean
Unless you want to mod and figure out make your phone awesome just flash other US firmware that uses gsm network only i think ATT only uses gsm and you can root to debloat ect.
Here's a method for rooting
https://forum.xda-developers.com/verizon-s7-edge/how-to/root-s7-s7edge-oreo-nougat-t3819616/amp/
I'm sure there's people in your surrounding area that are into androids and rooting that understand and can help you figure things out if you know any one woth a G930F/G935F INS/INU/PAK thatd be awesome. If your imei number is truly gone from your phone its should still be on the back of the phone
I know this isn't the best help but you aren't the first post I've seen of Pakistanian with US S7 tryjng to figure it out.. idk if he ever did but if you learn you can help others as well
*note: when I say change csc I don't mean flashing firmware in odin, that is impossible. I mean porting it yourself with root like in the link below this one
*another note: I am not saying use the link below as anything other than an example because again that link was developed for Eynos phones and not your snapdragon so it probably wouldn't work but just so you have an idea of csc
forum.xda-developers.com/s7-edge/development/utility-flashable-csc-selection-30-t3392957/amp/

Calling not working

Backstory: My sister bought Samsung Galaxy S8. She lives in Canada and after using it for a while, she sent it to me. I live in India and i factory resetted the phone, put my jio sim in and to my surprise it didn't work.
So my problem is, how do I make my sim work with this phone.
Model name: SM-950W
Android version: 9.0
CSC: KDO
No root
Things I have tried:
- restarting with sim in it
- turning on and off VoLTE option
- changing bands with some makeshift methods
- installing jioPhone application (this worked, but it is very messy as I need to have my mobile data turned on, and I can't use my Wi-Fi with it. So that's a major issue)
Please someone find a solution because I really can't make do without it ;-;

It looks like this question has been asked before. Remember to search before posting.
As for your problem, see this thread. The fix that has worked for many people is here.