Once in a while, we feel adventurous enough to unlock our phones' bootloaders and flash custom everything. Later on, however, we realize that we actually liked our phones a lot better when they were still running stock. Good thing we have handy-dandy Android forums with awesome developers who can help us with our dilemma. XDA Developers member MyComputerDoctor has shared his technique on how to get back the HTC Droid DNA ADR6435′s stock OS up and running.

After all the trouble you went through using the Droid DNA exploit to unlock your phone's bootloader, you might wonder what type of exploit you'll have to go through just to relock it. Don't worry though, the steps to relocking your phone's bootloader isn't as difficult as you might think. Just follow the steps below to relock your bootloader and return to stock software version 1.15.605.4. If you change your mind about liking stock, you can also re-unlock your bootloader without having to repeat the Droid DNA exploit.

This guide shows you how to relock the bootloader of the Droid DNA ADR6435.

Warning

• The instructions in this guide are intended for use with the HTC Droid DNA, model number ADR6435. Applying these instructions on another device or model may produce undesired outcomes.
• The information in this guide is provided for instructional and educational purposes only. There is no guarantee that these instructions will work under your specific and unique circumstances.
• Use these instructions at your own risk. We shall not hold any responsibility or liability for whatever happens to you or your device arising from your use of the info in this guide.
• Read and understand the whole guide first before actually performing the instructions.

Requirements

• HTC Droid DNA ADR6435 with an unlocked bootloader.
  • Check out our guide on how to unlock the Droid DNA’s bootloader.
• A Windows PC.
• Android Software Development Kit installed and an up-to-date Android Debug Bridge setup on your computer.
  • Here are our guides on how to install the Android SDK and set-up Android Debug Bridge on your computer.
• Download the HTC RUU Executable file (RUU_DLX_WL_JB_45_VERIZON _WWE_1.15.605.4_Radio_1.00.00.1023_3_NV _VZW_1.98_002_release_290923_signed.exe,  md5sum: a8246fae48ef00dbf3b2d7aa1a2a0090).
  • Original Link
  • Mirror Link
• Make sure your device's battery still has at least 70% power. You don't want the device to shut down in the middle of the procedure.
• Backup all personal data on your phone to make sure you have a copy of your personal data (e.g., contacts, SMS, MMS, Internet settings, Wi-Fi passwords, and the like) in case the procedure in this guide erases such data.
  • For backup tips, check our guides on how to sync your data to the cloud and how to create local backups of your mobile data.

Instructions

Relocking and returning to stock

1. Turn your phone off.
2. Boot into Fastboot Mode. Hold and press the Power button and the Volume Down key until the phone enters Bootloader Mode. Navigate to the Fastboot option using the Volume keys and select the option by using the Power button.
3. Connect your phone to your PC.
4. Open a command prompt on your PC.
5. Check whether your PC recognizes your phone. You will find your phone's serial number after you have typed the following in the command prompt:
   • fastboot devices
6. Relock your bootloader by entering the following command at the command prompt:
   • fastboot oem lock
7. Once you have relocked your device, your phone's bootloader will indicate that it has been “RELOCKED.”
8. Reboot the phone back to Fastboot Mode.
9. On your PC, open the RUU executable file using administrative privileges and follow the instructions.
10. Once you have completed the process, your phone will reboot to stock.

Re-unlocking after relocking

1. Turn your phone off.
2. Boot into Fastboot Mode. Hold and press the Power button and the Volume Down key until you enter Bootloader mode. Navigate to the Fastboot option using the Volume keys and select the option by using the Power button.
3. On your PC, copy the unlock token that you received from HTCdev the first time you unlocked your Droid DNA to the same folder where your Fastboot executable file is located.
4. Connect your phone to your PC.
5. Open a command prompt on your PC.
6. Check whether your PC recognizes your phone. You will find your phone's serial number after you have typed the following:
   • fastboot devices
7. Flash the unlock token by typing the following in the command prompt:
   • fastboot flash unlocktoken Unlock_code.bin
8. Your phone will restart. Once it's done restarting, turn your phone off.
9. Reboot the phone to Fastboot Mode. HBOOT should indicate that your Bootloader has been “UNLOCKED.” From here you can flash an unlocked kernel or custom recovery.
   • Note: If this does not work the first time, repeat steps 4 to 10 and make sure to use the unlock token you received from HTCdev for your Droid DNA.

Well done! You have just relocked and unlocked your HTC Droid DNA ADR6435. Now you can choose how you want to experience your Droid DNA and switch to stock and back without worries. Have fun!