How To Fix A Bootloop

So you must have googled about why your Android phone has refused to come up and gotten the terms such as “Bricked” or “Bootloop” as response to your search queries.  Most people use the term “brick” wrongly as well as “bootloop”. By the time you are done going through this article, fixing a bootloop will be a piece of cake for you.

So what do we mean when we say a Phone is in  a Bootloop?

A bootloop simply means when you phone attempts to restart itself over and over, endlessly refusing to actually boot up. Phones with “boot loop” problems will attempt to restart endlessly, often until the battery is completely drained. In the event of such a problem, there are a few things you can do, but do note that the “boot loop” is often a fatal condition for a device when common remedies fail to resolve it. A phone that is stuck in a bootloop is not “bricked” – point of correction nor is a phone that only boots into recovery. These are things you can usually fix, and they’re a lot more common than a truly bricked phone. If your phone is really bricked, you Probably won’t be able to fix it yourself without the assistance of a tech engineer or guru.

Why Does This Happen ?

So, why do smartphones boot-loop? There are a number of potential causes.

  • The device’s internal storage becomes damaged or corrupt
  • A failure in system update application (probably as a result of the above)
  • User attempts to apply custom software (a custom ROM, for example) incorrectly
  • Device is physically damaged by water, electricity, or some other external force
  • A malfunctioning or malicious 3rd-party app prevents the device from booting

These will cover the most common causes of the “bootloop” issue. The second one is, based on our observation, probably the most likely reason you’re here: your phone installed a new system update / upgrade, and after the installation, the phone rebooted over and over. Your instinct is obviously to blame the update: something has gone wrong, and the update your manufacturer or carrier provided is somehow “breaking” your device.

How Do I Fix This?

Well there are a variety of ways to fix a bootloop depending on what triggered it. Nevermind, I’ll be touching all of them in this article. Scan through this post with all interest if you find yourself in such a situation.

Step 1

Start by removing the device’s battery and wait for a few minute’s before putting it back in your phone.
OR Switch off for non-removable battery phones for five to ten minutes so it can remove any charge that is left in the phone and to initiate a complete power-cycle once you insert the battery.
Now Boot the device into Recovery Mode by pressing and holding the relevant shortcut keys for your device. For instance, most Samsung devices can boot into Recovery Mode while pressing the key combination Volume Up, Home and Power (for tablets it is Volume Up and Power). If using a HTC phone, boot into HBOOT first by tapping Volume Down and Power button together and then browse to Recovery using Volume Up/ Down buttons. If you cant get it to boot in Recovery you can always use (ADB) and type in the command] > adb reboot recovery <— Hit Enter now your Device will reboot into recovery mode. If your not familiar with adb or even know what adb is there is a link on the bottom of this page for the sdk download and a gude on the adb.

Step 2

Now browse and select the option Wipe Data/Factory Reset in Recovery Mode.Check if the device can now boot into the newly installed ROM or firmware. If not, then perform Wipe Cache Partition And Return to the main Recovery menu and reboot the device by choosing Reboot System Now option.After Flashing or Installing a New ROM and If the device is already rooted with ClockworkMod Recovery (CWM) installed, then do the following steps (1) Remove you’r battery and reinsert it after 30 seconds. (2) Boot the device into CWM Recovery by pressing and holding Volume Up, Home and Power buttons together. NOTE: The key combination may vary depending on your device model.So, CONFIRM BEFORE YOU PROCEED. (3) Now Go to Advanced option in Recovery menu and choose Wipe Dalvik Cache. Then perform Wipe/cache under Mounts & Storage. Reboot the device and check if the boot loop issue is resolved. If not repeat the above three steps, but perform both Wipe/data and Wipe/cache under Mounts & Storage before rebooting.

Step 3

After Setting an Incorrect File Permission.The Android operating system (OS) works on file permissions and hence incorrectly set file permissions may permanently damage or soft brick your device. Here are some of the commonly used file permissions:- 644 (RW-R-R) – (this is most common system permission, it exists in /system/app, /system/framework, /system/etc, /system/lib and allot of separate files) – 755 (RWX-RX-RX) – (mainly used for /system/bin) – 777 (RWX-RWX-RWX) – (used for scripts inside /system/etc/init.d and busybox files)
To fix or reset any of these file permissions, do the following:Boot the device into CWM or TWRP recovery Go to Advanced option.Click Fix Permission and confirm the action. After Restoring a Backup.If the bootloop error occurs immediately after restoring a Nandroid Backup, follow the steps on -(#:2)- to fix it. If everything else fails, just try re installing the original ROM or flash the first official firmware.

Using ADB (Android Debugging Bridge)

ADB can be used to access the phone while booting, but note that some bootloops make it impossible to use ADB since they do not go further than the Manufacturer logo.

The only tricky part about using ADB with bootloops is that you have to do it on the right time, this is different from every device, but normally it’s after the manufacturer logo that the partitions get mounted. The easiest way to enter your phone in this part is using a batch script that monitors the state of your device and connects directly when possible.

Use these scripts in ADB mode;
1 @ECHO off
2 cd /d %~dp0
3 echo.
4 echo Waiting for device…
5 adb wait-for-device
6 echo.
7 adb -d shell stop
8 adb push mycwmfix.zip /sdcard/mycwmfix.zip
9 adb reboot recovery

Linux Version (ondemand.sh):

1 #!/system/bin/sh
2 echo ” ”
3 echo “Wating for device…”
4 ./adb wait-for-device
5 echo ” ”
6 ./adb -d shell stop
7 ./adb push mycwmfix.zip /sdcard/mycwmfix.zip
8 ./adb reboot recovery

This script will wait for the device to become ready, when it’s ready it freeze the device, so the script has more time to push the file (instead of keep rebooting). Then it will push the specified cwmfix zip to your sdcard, and after that it will reboot in recovery so you can install the cwm fix you made. You can also make an batch script that pushes the files automatically to your phone, here is an example:

(1 @ECHO off
(2)cd /d %~dp0
(3)echo.
(4)echo Waiting for device…adb wait-for-device
(5)echo.
(6)adb -d shell stop
(7)adb -d shell su -c “mount -o remount rw /system”
(8)adb push framework-res.apk /system/framework/framework-res.apk
(9)adb -d shell chmod 644 /system/framework/framework-res.apk
(10)adb push SystemUI.apk /system/app/SystemUI.apk
(11)adb -d shell chmod 644 /system/app/SystemUI.apk
(12)adb reboot

(13)Linux version:

1#!/system/bin/sh
2echo ” ”
3echo “Waiting for device…”
4./adb wait-for-device
5echo ” ”
6./adb -d shell stop
7./adb -d shell su -c “mount -o remount rw /system”
8./adb push framework-res.apk /system/framework/framework-res.apk
9./adb -d shell chmod 644 /system/framework/framework-res.apk
10./adb push SystemUI.apk /system/app/SystemUI.apk
11./adb -d shell chmod 644 /system/app/SystemUI.apk
12./adb reboot
This script will wait for the device to become ready, when it’s ready it freeze the device, so the script has more time to push the file (instead of keep rebooting). Then it will push framework-res.apk and SystemUI.apk to the directory it belongs to, after that it changes the permissions of the files to RW-R-R (644) and then it will reboot.

Please note that on some devices the command “su -c” cannot be used after using the “stop” command, it gives an error then (Segmentation Fault).
What you can do to prevent this is adding “adb remount” just under the “adb wait-for-device” line, and remove the “adb -d shell su -c “mount -o remount rw /system” line.
Save the script and run it again.

For HTC Phones: HTC phones can flash stock ROMs, known as RUUs, right from the phone’s bootloader. You’ll need to Google around for your device’s specific RUU file, but once you download it, save the ZIP file to your SD card, and rename it (to something like PG05IMG.zip—the download page for the RUU file should specify which filename is required), booting up your phone should automatically flash the stock ROM from HBOOT, HTC’s bootloader. Video http://www.youtube.com/watch?feature…&v=tE8BiIFUOpk

For Samsung Phones If you’re using a Samsung Galaxy phone, you can use a tool called Odin to reflash an OPS file, which is a stock ROM that will return your phone to factory settings. You’ll need a Windows machine and a copy of Odin, which you can find by Googling around the net (as its not an official tool) check out The Unlockr’s guide to using Odin to familiarize yourself. You may need to Google around for your specific device’s OPS file and instructions.
Video http://www.youtube.com/watch?feature…&v=5s70dwNgdD8

Verizon Galaxy S3 Bootloop fix using Odin
The Verizon Galaxy S3 has to be the most problematic variant of the Galaxy S3. If the locked bootloader on it wasn’t enough, many users have seen their Verizon Galaxy S3 get bricked and stop booting after trying to flash a custom ROM.

You will have to download some files first. They include;

Samsung USB Driver V1.5.14.0 For Android Mobile Devices

ODIN

VRALEC.bootchain.tar.md5

BOOTLOADER-I535VRALF2-618049-REV09-user-low-ship.tar-2-.md5

stock.vzw_root

Procedure
Make sure phone is off. Boot into download mode. To do so, hold down the Volume Down, Home and then the Power buttons together until a Warning!! message is displayed on the screen. Here, press Volume Up to enter download mode. A green Android and the text Downloading will be displayed on the screen.
Now, open Odin by clicking on the Odin3 v3.07.exe file in the Odin307 folder which you obtained after extracting Odin307.zip
In Odin, click on the PDA button, then select the VRALEC.bootchain.tar.md5 file that you downloaded.
Important Untick every option under the “Option” section (on the top left of Odin), except F. Reset Time. Check the screenshot below for reference.

Then, connect the phone to the computer with the USB cable and wait for Windows to finish installing drivers. Odin will say Added!! in the message box on the bottom left if the phone is detected successfully. If not, make sure the drivers are installed and also try using a different USB port – preferably a USB port on the back if using a desktop computer.
Click on Start to start flashing the VRALEC.bootchain.tar.md5 file on the phone.
Wait till flashing is complete and you get a PASS message in Odin. When that happens, disconnect the phone from the computer, but DON’T turn it off and let it stay in download mode. Also close Odin.
Reconnect your phone to the computer (while it is in download mode). Open Odin again.
This time, click the PDA button and select the BOOTLOADER_I535VRALF2_618049_REV09_user_low_ship.t ar.md5 file that you download
Also, again untick every option except F. Reset Time in Odin. Then, click on the Start button to start flashing the BOOTLOADER_I535VRALF2_618049_REV09_user_low_ship.t ar.md5 file on the phone.
When flashing is complete and you get a PASS message, disconnect the phone and close Odin. But keep the phone in download mode, don’t turn it off.
Open Odin again and also reconnect the phone to the computer.
Click the PDA file and select the stock.vzw_root66.tar file that you Downloaded
[Important] Select the following three options in Odin on the top left: Auto Reboot, F. Reset Time, Nand Erase All. Check the screenshot below for reference.

Click Start to start the flashing process. Once the flashing is complete and you get a PASS message, the phone will automatically reboot. Disconnect the phone from the computer.
The phone will still not boot up completely. Now, remove the battery on the phone, then re-insert it. Don’t turn it on.
Now, boot into recovery. To do so, press and hold the Volume Up + Home + Power buttons together till the screen turns on, then let the buttons go. The phone will boot into recovery in a few seconds. You will see a few error messages in recovery, which is normal.
In recovery, use the volume buttons to scroll up/down and the home button to select options.
Select wipe data/factory reset, then select Yes on next screen to confirm. Wait a while till the data wipe is complete (this will NOT delete your personal files on the SD cards).
Select wipe cache, confirm, then wait for cache wipe to be completed.
Then, select reboot system now to reboot the phone.
The phone will now boot up properly into Android and is fixed, and you will be able to use it now..

HOW TO UNBRICK YOUR DEVICE

REQUIREMENTS TO UNBRICK YOUR PHONE

First install java on your pc if you haven’t java go to Java site and install it.
download one-click Unbrick tool
window users will need .rar/.zip extractor software , you can download free all in one 7zip extractor form here.

FOLLOW THESE INSTRUCTIONS CAREFULLY

1. Right-click on the One-Click.jar file, move down to option “7-zip” and then select “Extract to OneClick”.

2. Now you will get a ‘OneClick’ folder.

3. Now copy ‘OneClick.jar’ file and paste it into the ‘OneClickheimdalloneclickresourcesHeimdallPackage’ folder.

4. Right-click on ‘oneclickloader.exe’ file and choose ‘Run as Administrator’.
5. Proceed with the installation of Heimdall.

6. After the installation is complete, you will see the the One-Click UnBrick interface.

Connect the phone to computer via USB and click on “unsoft brick” button to recover your bricked android phone.

I hope this helps you solve your bootloop problems. Please feel free to comment on any misunderstandings whatsoever you might have concerning this article.

 

I am a Tech Enthusiast.