in ,

Galaxy S7 won’t send SMS at random, keeps losing signal, “not registered on network” error, other issues

Hello everyone! Here’s the latest #GalaxyS7 article for you. This post addresses more S7 problems so please take your time to go over them. We will continue to publish similar posts in the future so keep watching for them.

If you are looking for solutions to your own #Android issue, you can contact us by using the link provided at the bottom of this page.

When describing your issue, please be as detailed as possible so we can easily pinpoint a relevant solution. If you can, kindly include the exact error messages you are getting to give us an idea where to start. If you have already tried some troubleshooting steps before emailing us, make sure to mention them so we can skip them in our answers.

Below are specific topics we’re bringing for you today:

Problem 1: Galaxy S7 keeps rebooting on its own, settings keep changing

I have had no issues with my phone up until today. My alarm went off on it, then it instantly restarted. When it turned back on it changed the theme back to the default one. So I changed it back thinking the issue would be over. My phone then restarted 4 more times later in the day. Each time resetting the theme, and changing random settings on my phone like the performance mode and default messaging app. The last time it happened it zoomed the screen in on the home screen so some apps didn’t appear on the screen and the ones that did were a lot larger than usual, it randomly changed back but I forget what I did to make it change back. It also changed the default messaging app so I changed it back to the app I wanted. Now I don’t get notifications on the lock screen that I have a message even though the settings are set to show me notifications in the lock screen when I do. How can I get it to stop doing this, cause its been going on all day and its really starting to worry me? — Harris

Solution: Hi Harris. If you can’t remember what you did differently (such as installing a new app or update) that might led to this situation, we suggest that you do a factory reset and proceed from there. If the problem is being caused by an operating system glitch or app, it should go away after a factory reset. Make sure to observe the phone for 24 hours after performing a factory reset. Do not install anything during this time. Doing so will give you enough time to observe phone’s behavior.

Below are the steps on how to factory reset your phone:

  1. Create a backup of your important files such as photos, videos, contacts etc. You can use Smart Switch for this task.
  2. Turn off your Samsung Galaxy S7.
  3. Press and then hold the Home and Volume UP keys, then press and hold the Power key.
  4. When the Samsung Galaxy S7 shows on the screen, release the Power key but continue holding the Home and Volume Up keys.
  5. When the Android logo shows, you may release both keys and leave the phone be for about 30 to 60 seconds.
  6. Using the Volume Down key, navigate through the options and highlight ‘wipe data / factory reset.’
  7. Once highlighted, you may press the Power key to select it.
  8. Now highlight the option ‘Yes — delete all user data’ using the Volume Down key and press the Power button to select it.
  9. Wait until your phone is finished doing the Master Reset. Once completed, highlight ‘Reboot system now’ and press the Power key.
  10. The phone will now reboot longer than usual.

If the symptoms you mention above will continue even after a factory reset, you can assume that the issue is due to bad hardware. Since there’s no direct way to know what specific hardware may be malfunctioning, your only option would be to have the phone replaced or repaired.

Problem 2: Galaxy S7 screen stays black and won’t turn on

Hello! I’m asking for your help on my husband’s behalf. He has a Samsung Galaxy S7 Edge. He was on his phone on Facebook, the battery was at 40% and connected to a battery pack charging and it suddenly went onto the Samsung Galaxy S7 Edge screen and frozen. He did a reboot pressing the volume up & power button together, it rebooted and then froze on the same screen. He tried a second time and it happened again. Third time it didn’t do anything at all. Black screen. We plugged it into the main charger just in case and no lights have come on to indicate it’s charging but when the battery pack is plugged into it the pack indicates a charge is being taken from it, the lights at the front show it. I tried rebooting it again, nothing. I tried going into safety mode, nothing. I read your troubleshooting article and tried almost everything but nothing worked (I didn’t try anything that would have resulted in going back to factory settings or resetting the phone entirely) please help if you can. — Holly

Solution: Hi Holly. To properly perform a soft reset, which is the equivalent of a “battery pull,” you are supposed to press and hold Volume Down and Power buttons (not Volume Up). If you’ve already tried this before attempting to contact us, the following are the other things that you must try:

  1. use another charger and USB cable
  2. try to restart the phone to alternate modes

Sometimes, a problem like this can be caused by a bad accessory so you want to ensure that the USB cable and charger you’re using right now are working 100%. Once you’ve made certain that it’s not the USB cable or charger, the only other thing that you can try is to see if your device can still power back on to other modes. Only then can you try to perform follow-up troubleshooting steps like:

  • wiping the cache partition,
  • factory reset via Recovery mode, or
  • flashing (via Odin mode)

Again, these items are only possible if the device will power on. If it remains unresponsive or dead, you must have it repaired or replaced.

Here are the steps on how to boot your S7 to alternate boot modes:

Boot in Recovery mode:

  1. Charge the phone for at least 30 minutes.
  2. Press and then hold the Home and Volume UP keys, then press and hold the Power key.
  3. When the Samsung Galaxy S7 shows on the screen, release the Power key but continue holding the Home and Volume Up keys.
  4. When the Android logo shows, you may release both keys and leave the phone be for about 30 to 60 seconds.
  5. Using the Volume Down key, navigate through the options and highlight ‘wipe cache partition.’
  6. You can either wipe the cache partition or do a factory reset when in this mode.

Boot in Download Mode:

  1. Charge the phone for at least 30 minutes.
  2. Press and then hold the Home and Volume DOWN keys, then press and hold the Power key.
  3. When the Samsung Galaxy S7 shows on the screen, release the Power key but continue holding the Home and Volume DOWN keys.
  4. Wait until the Download screen appears.
  5. If you can boot the phone in download mode but not in other modes, that means that your only way out may be to flash a stock or custom firmware.
  6. Use Google to look for a guide on how to do it.

Boot in safe mode:

  1. Charge the phone for at least 30 minutes.
  2. Press and hold the Power button.
  3. Once the ‘Samsung Galaxy S7’ logo appears, release the Power key and immediately press and hold the Volume Down button.
  4. Continue holding the button until the phone finishes rebooting.
  5. Once you see the text “Safe mode” at the bottom left corner of the screen, release the Volume Down button.
  6. The only difference of safe mode from normal mode is that the former prevents third party apps from running. If you can boot the phone in safe mode but not in normal mode, uninstall all apps until the issue (that prevents you from booting normally) is eliminated.

Problem 3: Galaxy S7 won’t send SMS at random

I’m not looking for a response, and don’t really want my message posted. Just FYI, in case it helps you. This is in regard to another user’s question: “I just purchase the new Galaxy S7 two days ago. I have noticed that a couple times a day, it will stop SENDING text messages. I restart the phone, and the issue resolves. I know this is a new phone, but I’m hoping that I can get some help with this. It’s annoying to do this 2-3 times a day. Thanks for your help.”

I’ve had this happen with, I think, all of my Galaxies (2, 4, 7) – It will just stop sending texts. Tries forever, then fails. Has happened to me numerous times in the past few days. In my experience… – Restarting the phone generally works, but often happens again a short time later – It happens while on both cellular and wifi, but sometimes seems to be triggered by going from wifi/no cellular to a cellular/no wifi area while trying to send the message – But the most consistent fix I’ve found is clearing up some storage (for me, photos) or deleting old text messages (PS, this page never completely loads, huge delays in response, worse the longer this message gets.) — JS

Solution: Hi JS. We know you expressed explicitly said not to publish your message but we can’t see any reason to do so. So, we apologize if we have to post it but we think it’s more helpful for Android community to see what you did to fix your issue. The more people know this workaround, the higher the chance of us helping other users. Our blog doesn’t exist to receive feedbacks from Android community in private. That’s the main reason why we don’t send our help via email. We want to make solutions public. As long as we won’t violate any privacy concerns, we are within our right to make communications with our readers public.

Problem 4: Galaxy S7 turns on but remains stuck in Samsung logo screen

First I had red LED with black screen, then when I show it to Samsung care they somehow turned off red LED but the screen remains black and phone did not boot. They said that it’s a motherboard problem and asked for a heavy fees so I did not get it fixed there. I tried every possible solution on internet but nothing works. No buttons responded and mobile did not turn on. Then after several days, randomly I plugged in the charger and screen showed phone charging icons. So, in my excitement, I turned it on normally. It started to boot but as soon as it reaches Samsung logo then after some time screen went blank and now blue LED is glowing. so now again my phone is having black screen but now with blue LED light glowing and button is responding. Please help me. As I have important data in my phone. — Kumar

Solution: Hi Kumar. Try to see if you can turn the phone on to alternate boot modes (refer to the steps above). See if you can boot to Recovery mode first so you can try cache partition cache and factory reset.

If you can’t, try to see if you boot to Download/Odin mode so you can attempt flashing the bootloader and/or firmware. Below are the general steps on how to flash a bootloader. The exact steps may vary for your phone model so make sure that you do extra research on how to do it. The provided steps below are only for demonstration purposes.

  1. Look for the correct firmware for your phone model and download it. Make sure that you select the right one. It should be the same exact firmware that ran previously on your device. We assume that you list down the firmware version somewhere. If you did not take note of it before, there’s a chance that you may pick the wrong one. As you may know now, using an incorrect firmware can cause complications so good luck with that.
  2. Let’s now say that you have identified the correct firmware. You then want to download it to your computer. The firmware file should have a bunch of files in it like AP_, BL_, CSC_, etc.
  3. Look for the file that starts with a label BL; this should be the corresponding bootloader file for this firmware. Once you’ve identified the bootloader file, copy it to your computer’s desktop or to any other folder that you can easily access.
  4. Proceed with the rest of the flashing procedure using the Odin program.
  5. In Odin, click on the BL tab and make sure to use the bootloader file you’ve identified earlier.
  6. Now, make sure that the “Device Added” status and its “ID:COM box” has turned blue before hitting the START button. This will initiate the flashing of your phone’s bootloader.
  7. Restart the phone once the procedure is finished.

If all these software solutions won’t work, or if your phone remains unresponsive at all, go ahead with motherboard replacement or repair.

Problem 5: Galaxy S7 screen is cracked and keep flickering, won’t turn on most of the time

This past weekend, I went to Mexico for a trip. My phone already has a cracked screen but still works perfect. I had my phone kinda like in between my legs and after we had crossed the border, my screen went black. Let’s say I wanna make a phone call. In order for me to do that, I would have to constantly turn my screen on and off again for about 5-10 mins straight before the screen finally appears and when it does, bottom quater of the screens flickers white. I turn brightness up all the way and flickering stops BUT if I lock the screen, another 10 mins of myself pushing the home and power button back and forth before screens turns on but flickers. Tried soft reboot and factory settings and nothing work — Jon

Solution: Hi Jon. Your phone is clearly having a hardware malfunction so we’re wondering why you haven’t tried having it repaired or replaced yet. For the benefit of everyone, the general rule in Android troubleshooting is simple, if factory reset won’t fix a problem, bad hardware must be to blame. You should resort to repair or replacement to resolve it. Don’t expect a software tweak will fix a bad screen, like the one you’re experiencing right now. If you’re lucky and the damage is isolated to the screen assembly only, repair should fix it easily.

Problem 6: Galaxy S7 messaging apps like Viber, Facebook Messenger, Whatsapp won’t work unless they are restarted

I have an S7 edge that i bought 2nd hand couple months old with receipt and all legit from seller. Phone is great however… my Viber, Facebook Messenger, Gmail accounts, Whatsapp…do not work unless i exit out and re-sign in. It’s so frustrating. I’m on my carrier Optus $2-a-day plan which is prepaid plan no longer available. When i went to Optus they seemed clueless and said its because my plan is 3G but edge is predominantly 4G bla bla…. What can i do because i now miss my crappy HTC one i used to have but it was basically on its last legs #sadface. — Livlualua

Solution: Hi Livlualua. Below are the things that you can try:

  1. Make sure that master sync is ON. This is done by turning on the Sync button in the status bar. Just pull the status bar on the screen and look for Sync button and make sure that it’s enabled.
  2. Delete affected apps’ cache and data. Depending on the cause, this troubleshooting step may or may not work. Refer to the steps below on how to do it for each app.
  3. Wipe the cache partition. The cache partition stores the a number of files but one of them is the system cache, which is a special set of files used by Android in loading apps. Sometimes, installation of apps and updates can corrupt the system cache, which, in turn, can also lead to all sorts of problems. Deleting the old system cache forces the phone to build a new one overtime so you don’t want to skip this step. It can be done safely without losing any user file like your photos, videos, etc.
  4. Factory reset. As the name suggests, this procedure will revert all software settings to their factory defaults. Most of the time, this procedure can effectively fix problems being caused by a software or app bug. If nothing will change however after doing it, you can bet bad hardware is to blame. If you don’t know how to do this, kindly refer to the complete steps above.

Below are the steps on how to delete an app’s cache and data:

  1. Open the Settings menu either through your notification shade (drop-down) or through the Settings app in your app drawer.
  2. Navigate down to “Apps”. This may be renamed to something like Applications or Application Manager in OEM skinned versions of Android 6 or 7.
  3. Once in there, click on an application.
  4. You’ll now see a list of stuff that gives you information about the app, including Storage, Permissions, Memory Use, and more. These are all clickable items. You’ll want to click on Storage.
  5. You should now clearly see the Clear Data and Clear Cache buttons for the application.

To wipe the cache partition, refer to the steps below:

  1. Turn off your Samsung Galaxy S7.
  2. Press and then hold the Home and Volume UP keys, then press and hold the Power key.
  3. When the Samsung Galaxy S7 shows on the screen, release the Power key but continue holding the Home and Volume Up keys.
  4. When the Android logo shows, you may release both keys and leave the phone be for about 30 to 60 seconds.
  5. Using the Volume Down key, navigate through the options and highlight ‘wipe cache partition.’
  6. Once highlighted, you may press the Power key to select it.
  7. Now highlight the option ‘Yes’ using the Volume Down key and press the Power button to select it.
  8. Wait until your phone is finished doing the Master Reset. Once completed, highlight ‘Reboot system now’ and press the Power key.
  9. The phone will now reboot longer than usual.

Problem 7: Galaxy S7 keeps losing cellular signal, “not registered on network” error

Hello. I came across your very helpful website and wondered if you have any advice on this. I have an S7 Galaxy that I bought secondhand about 10 months ago. It is not locked to any operator.

About 10 days ago I started getting a “not registered on network” message, which meant I was unable to phone or send/receive messages. I have tried the following things:

  • Put the SIM card in another phone. It worked fine.
  • Soft reset
  • Restored my cellphone to factory settings.
  • Checked to make sure I have all the latest software updates.
  • Went into Settings>mobile networks … searched for available operators and tried connecting to them. I have done this multiple times. Sometimes, it works and I am briefly re-registered on the network, am able to call and send/receive messages. However, after a short time the problem reappears.

Sometimes I mysteriously get re-connected to the network without doing anything. Even when it shows I am registered on the network, sending messages is extremely slow and I sometimes have to re-try a couple of times before it goes through. I went into the local shop of my cellphone operator (I live in France, the operator is Bouygues). They say it is a problem with my cellphone, unrelated to their network. I’m thinking this might be a problem with the SIM card reader — perhaps a bad contact. Do you have any thoughts on this? Am trying to find a fix that would not require buying a new phone, since everything else on the phone seems to work fine. — Carol

Solution: Hi Carol. If SMS and other network-dependent activities work in another phone if you insert your SIM card to it, that’s a clear indicator that the problem is device-related. Do a factory reset and observe how SMS works without installing an app or update for 24 hours. If the problem continues to occur, get a new phone.

 


Engage with us

If you are one of the users who encounters a problem with your device, let us know. We offer solutions for Android-related problems for free so if you have an issue with your Android device, simply fill in the short questionnaire in this link and we will try to publish our answers in the next posts. We cannot guarantee a quick response so if your issue is time sensitive, please find another way to resolve your problem. 

If you find this post helpful, please help us by spreading the word to your friends. TheDroidGuy has social network presence as well so you may want to interact with our community in our Facebook and Google+ pages.

Leave a Reply

Your email address will not be published. Required fields are marked *

Samsung Galaxy S4 Auto-Rotate Not Working

Samsung Galaxy S7 Edge Can’t Get Out Of Recovery Mode Issue & Other Related Problems