Galaxy S7 keeps showing “Unsupported SD Card” error, other issues

Hello Android community! Welcome to yet another post that addresses issues about the #GalaxyS7 series. We cover 6 issues that we receive from some of our readers. We hope that this is helpful.


Here are the specific topics in post today:

  1. Galaxy S7 keeps showing “Unsupported SD Card” error
  2. Samsung Galaxy S7 Edge dual-SIM model from T-Mobile won’t allow second SIM to access network when T-Mobile SIM is inserted
  3. Galaxy S7 poor battery performance
  4. Galaxy S7 takes a long time to send and receive photos via stock messaging app
  5. Galaxy S7 Edge won’t perform a factory reset
  6. Galaxy S7 Edge encryption not working properly

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, or you can install our free app from Google Play Store.

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.

Problem #1: Galaxy S7 keeps showing “Unsupported SD Card” error

My device has been showing an “Unsupported SD Card” message in my notifications for about a month. My device was running flawless up until this occurred. Quickly, I am not sure about the android version I am running. The device is an Android Galaxy S7 and I had it pre-ordered. Maybe that information will keep us both on the right track if you guys send the troubleshooting information back to me.

Basically, device is running fine. I started receiving these messages in the notifications drop down. When I tap on the message I was hoping it would take me to a setting that could possibly be set incorrectly, or maybe an advanced setting that I could just troubleshoot myself. Unfortunately, tapping on the message does nothing.

I have tried the following:

  • Restart Power off/back on after 10 sec. 
  • Removing the SD card with the device powered down, reinserting and powered up.
  • Plugging into a PC to see if SD card is visible (which since this message started showing, it is not).

The last couple of weeks, the message does not appear any longer, yet I still do not have a mounted SD card. Before I use useless apps to check my SD card, I was hoping to get some feedback from you guys. If you could please respond, possibly send me some type of sequence of troubleshooting I could try before having to take it to the T-Mobile store (which from my experience is a waste of time). Please let me know. Regards. — Mike

Solution: Hi Mike. You don’t need to go to your carrier’s store for this one. If a computer can’t detect the SD card card either, that’s an obvious indicator that said SD card has stopped working. We won’t enumerate why an SD card can stop working all of a sudden as that’s another topic. The important thing is that you’ve already established the fact that the SD card has become unreadable for some reason. If you want to check further, insert it to another phone and see if you’ll get the same result. If your next question is, “can there be anything that you can do to make it work again?” the answer is NO.  Accept the fact that everything you stored in that card is gone. You simply have to move on by getting a new SD card.

Now, if another phone or computer will still be able to  miraculously read the SD card, make sure that you do the following (in this order):

  • Create a backup of your files.
  • Reformat the SD card using that computer or phone.
  • Re-insert the newly reformatted SD card to your Galaxy S7 and reformat it again.

Problem #2: Samsung Galaxy S7 Edge dual-SIM model from T-Mobile won’t allow second SIM to access network when T-Mobile SIM is inserted

Hello Droid Guy. I am new to the world of Droid as I have just switched from Apple. I have purchased a Samsung Galaxy S7 Edge dual SIM. I did this because I live in West Africa. I am an American working here and I have a T-Mobile account in the US that allows me to use that phone here in Ghana. I also, for work purposes, need a local phone and number. So instead of owning two phones, why not have one phone and two SIMs. The issue is that my T-Mobile SIM for some reason causes my local Ghanian SIM to not be able to hold a network signal. I tried resetting network setting and even did a hard reset and it still did not work. When I took out the T-mobile SIM and just ran two SIMs from Ghanian services, the phone works fine. I would like to be able to use my T-Mobile SIM as well as a local carrier SIM if possible. Any help will be appreciated. — Casey

Solution: Hi Casey. We’re not sure if the problem is a T-Mobile firmware restriction or not so the best party that can help you with this one is T-Mobile itself. We are not aware of any Samsung-related restriction that prevents another SIM from working when inserted to the second SIM slot. T-Mobile’s Android version may be programmed to forcefully lock the phone to their network whenever their SIM card is inserted. Please contact T-Mobile and ask direct assistance from them.

Problem #3: Galaxy S7 poor battery performance

I need your Samsung expertise please. I just bought a brand new Galaxy S7 and I feel the battery life is well below what it should be. I’ve done all the usual tips like disabling app refresh, syncing, brightness, etc., and even had the power saver on all the time. doing no streaming and barely using it yet when i take it off full charge but it’s already sitting at 10hrs remaining. Surely, for the brand new Galaxy S7 it should be better than that.

The main reason I upgraded was battery life but it isn’t even performing better than my iPhone 5. Could I have a faulty battery or is there something I should do? I’m very conservative at the moment with apps and brightness etc and its still average. I just want to be able to use it throughout the day with an average person’s usage and expect to come home with enough battery. After 3 days the battery is going down at an average of 10-15% per hour. — Shaunmcsweeney

Solution: Hi Shaunmcsweeney. Compared to its immediate predecessor, the Galaxy S6, the newer Galaxy S7 has a bigger battery capacity at 3000mAh. It is thus expected to have better battery performance than the other phones in this series. We can also attest that this is also our observation with our own Galaxy S7. Our Galaxy S7 can last for over 14 hours a day on average and that’s after normal to heavy usage. We are conservative when it comes to screen brightness though and we always make it a habit of turning off all sync features of apps and phone so that may have helped. Still, we don’t know how long you expect your phone’s battery to last in a day but if you’ve already tried all the tips and tricks in minimizing battery consumption, then there’s nothing more that we can do to help you. Call Samsung and have them replace the phone.

Problem #4: Galaxy S7 takes a long time to send and receive photos via stock messaging app

If I take picture with the camera I can’t always send the pictures out. I have the camera setting on the lowest resolution possible and it still takes forever to send one picture let alone 3. My S4 sends faster. Pictures come thru most of the time but some come thru with only half a picture and nothing else. Others come thru with the picture and 3/4 see thru green color and some look like a puzzle. I exchanged the phone and it worked good for the first few days and then with a new update this morning the issues have returned.

I’m now using an App called WhatsApp and when I send pictures that way they are gone within a few seconds and clear as a bell. Why doesn’t the Samsung Message app do the same thing? I might add I have a 3G Micro tower in the house and internet is full bars so shouldn’t the pictures be going thru the 3G cell tower hooked to the internet? — James

Solution: Hi James. The cause of the problem can be one of the following things:

To check if the issue is isolated to the Samsung Messaging app only, make sure that you wipe its cache and data. To do that, follow these steps:

  • Open the Settings menu.
  • Tap Apps (some versions may show Applications or Application Manager).
  • Tap the Messaging app.
  • Tap Storage.
  • Tap Clear Cache, then Clear Data (in this order).

If the problem remains after you’ve cleared the cache and data of the app in question, the next troubleshooting is to refresh the system cache. Here’s how:

  • Turn off the device.
  • Press and hold the following three buttons at the same time: Volume Up key, Home key, and Power key.
  • When the phone vibrates, release the Power key but continue to press and hold the Volume Up key and the Home key.
  • When the Android System Recovery screen appears, release the Volume Up and Home keys.
  • Press the Volume Down key to highlight ‘wipe cache partition.’
  • Press the Power key to select.
  • When the wipe cache partition is complete, ‘Reboot system now’ is highlighted.
  • Press the Power key to restart the device.

Refreshing the cache will force the phone to delete the possibly corrupted or outdated one and create a new one. If this won’t help either, the next best thing that you can do is factory reset. Here’s how:

  • Turn off your Samsung Galaxy S7.
  • Press and hold the Volume Up, Home and Power keys together.
  • When the device powers on and displays ‘Power on logo’, release all keys and the Android icon will appear on the screen.
  • Wait until the Android Recovery Screen appears after about 30 seconds.
  • Using the Volume Down key, highlight the option, ‘wipe data/factory reset’ and press the Power key to select it.
  • Press the Volume Down button again until the option ‘Yes — delete all user data’ is highlighted and then press the Power key to select it.
  • After the reset is complete, highlight ‘Reboot system now’ and hit the Power key to restart the phone.

Problem #5: Galaxy S7 Edge won’t perform a factory reset

Hi There. My S7 Edge was having problems with frequent lockups, garbled screen and spontaneous resets. Now I wiped the cache and ordered it to go to factory settings. When rebooting, it now says in a nice blue screen it is updating/installing the new firmware and after a while ‘erasing’. Then a falling Droid with exclamation is seen. it collapses into Recovery mode with an error after formatting: Formatting /data E: Format_volume: make ext4 failed on /dev/block/platform/155a0000.ufs/by-name/USERDATA with 1 (I/O error) — Set factory reset done… — Copying Media files... — Preload checkin… Datawipe failed. E: Data wipe failed — Applying Multi-CSC… Applied the CSC-code : PHN Succesfully applied Multi-CSC — Set factory reset done — copying media files — preload checkin… and that’s it. It won’t boot anymore and everytime I reset the same thing happens. Any suggestions? — Eric

Solution: Hi Eric. A normally working Galaxy device should be able to execute the complete factory reset sequence. That your phone is doing otherwise is an obvious indication that something’s wrong with its software. You must call Samsung and secure a replacement unit.

Problem #6: Galaxy S7 Edge encryption not working properly

I have a Galaxy S7 Edge and I have got a 128G SD card. The SD card was encrypted since I installed it the first time. When the new software was released, I went ahead and installed it. I turned off my phone couple of days later and turned it back on and chose to encrypt the SD card from the pop up screen. It’s been encrypting for the past week now! Knowing that, I turned the phone off again to decrypt the SD card but that didn’t work as it took a lot of time with no result at all. Now, it’s still encrypting and it seems like I lost my files and can’t access them on any computer since they were encrypted. I would really appreciate your help in this one. — Hsamus

Solution: Hi Hsamus. Encryption is a good way to secure important files but one of its downsides is the fact that no other device will be able to read the encrypted device afterwards. This means that even if you’ll stop the device at this time and try to recover your files by inserting the SD card in a computer, you’ll still be unable to access the contents. Even if the SD card is still working, no other device will be able to decrypt it.

The best thing that you can do right now is to wait until the device finish the encryption process (though 1 week is way too long). The most likely scenario now is that the SD card has been corrupted and the encryption process is either going in a loop or may have already stopped although your S7 does not indicate so. Give the device a few more days to try and do its job. If nothing changes after that, accept the fact that the SD card has stopped working and your files gone. There’s no way you’ll be able to recover your files back even if you insert the SIM card on another Galaxy S7 because of the way encryption in Samsung devices work. The actual decryption key is device-specific and cannot be transferred to another one. Even using the same password on the same exact phone model won’t work.

You’ll can continue using the same SD card in another device or the same phone by erasing everything off it via the format option.

Also, since you noticed that the issue started after an update, you might want to consider doing a factory reset to start fresh. This will help minimize bugs from emerging and possibly help in deleting existing ones.


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.

Posts You Might Like

Leave a Comment