What to do if Galaxy S8 Plus is stuck in boot loop during an OTA update

Although majority of devices that download and install updates over-the-air do so successfully, some unlucky few may hit a snag. In today’s #GalaxyS8Plus troubleshooting article, we tell you what you can do if your own S8 Plus would be unable to boot up normally, or if it gets stuck in an unending boot cycle or boot loop.

Today’s problem: Galaxy S8 Plus stuck in boot loop during an OTA update

AT&T Galaxy S8+ stuck in bootloop. It will get past the Samsung Galaxy S8+ logo and the Samsung logo that follows. It then gets stuck for around 5-10 seconds on starting android and reboots. Per you article I wiped the cache partition and factory data reset from recovery mode. It hasn’t fixed it. Safe mode stalls at the “starting android” screen as well. It all started with an OTA update a few days ago that got my phone stuck in the bootloop. What can I do? Any help is greatly appreciated! — Joshua

Solution: Hi Joshua. The only official suggestions by Google and Samsung in this case are cache partition wipe and master reset. If the problem was not resolved after doing them before contacting us, then the next ideal step is to ask professional help from Samsung. Samsung devices don’t usually get bricked after installing an OTA update so if they occur, there must be a reason unique to your system causing it. Since it’s impossible to know what that unique reason might be, Samsung will most likely just wipe the phone and reflash stock firmware to it. Flashing is inherently risky so if Samsung mess it up, they’ll usually end up replacing the device.

If you want to accept the risks involved in flashing, you can attempt to do it yourself. There are two things that you can do:

• flash the bootloader with stock version, and
• flash the firmware with stock version.

Before you do any or both of these options, be sure to download the correct firmware build for your particular device. Using an incorrect Android build can potentially damage the software for good. Also, flashing the firmware, even if you’ll be using an official version, will most likely end up voiding your device’s warranty. If you’ll decide later to send the device to Samsung and  they’ll find out that the software had been tampered with, they’ll refuse to even touch your device.

Below are the general steps on how to flash a Samsung Galaxy device. Exact steps may be a little different for your particular model so we strongly recommend that you find other authoritative guides for your S8. Make sure that you do enough research about the subject before doing the solutions below.

Keep in mind, flashing may or may not help in this case. Do them at your own risk.

How to reflash the bootloader of your S8

This procedure is basically identical to how you flash the software/firmware of your device. The only difference is a step where you have to pick BL (stands for bootloader) component of the entire firmware package.

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.

Manually install official stock firmware

If reflashing the device’s bootloader back to stock won’t help, you should then consider flashing stock firmware to your device. We suggest that you use the original firmware that came with your device when you first unboxed. This is most likely Android 7.0 (Nougat). As mentioned above, be sure to use the correct firmware build to prevent causing permanent damage to the device.

1. Download the correct firmware build. The firmware build should either be in .tar or .tar.md5 format.
2. Turn off your S8 and boot it to Odin or Download Mode.
3. Connect your device to your computer (where you previously install Odin program to). Make sure that your computer detects your S8.
4. As soon as you connect the device the ID:COM port on Odin will turn Blue or Yellow depending on the Odin version. You’ll also see “Added!!” message to indicate successful connection.
5. In Odin program, select the AP button.
6. Navigate to the firmware file and select it.
7. If you’re using a firmware build with multiple firmware (AP, BL, CP, CSC, and .PIT files), make sure to add each component manually in their respective field.
8. In the Options section, make sure that only Auto Reboot and F. Reset Time boxes are checked. Do not use PIT file unless it’s clearly stated in the guide you’re following. Using it will re-partition your device, which may result to serious issues.
9. Click Start button.
10. If flashing is successful, it should be indicated by PASS or RESET! Message.
11. Wait for your S8 to restart.

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