Here’s an updated method for downgrading your HBOOT 1.50 to 1.40 on your HTC Evo 3D. (older method here)
Step 1. Make sure you are on Software number 2.17.XXX.X.
Step 2. Take the battery out and in, then hold down Volume Down and Power button together for 5 seconds to get into bootloader.
Make sure your phone either says “LOCKED”, “RELOCKED” with “S-ON” and HBOOT 1.50. If not, follow this guide on how to unroot your Evo 3D first.
Step 3. Reboot your Evo 3D normally then make sure “USB Debugging” is checked ON under Settings->Applications->Development.
Step 4. Connect micro-USB cable from your Evo 3D to your computer and make sure the USB connection is set to “Charge Only”.
Step 5. Open up Device Manager in Windows and make sure you see something like “MY HTC” or “ADB Interface”. If you don’t, make sure to install HTC Drivers.
Step 6. Download hbootdowngrade217.zip, unzip, and put it in a folder called hbootdowngrade217 in your root directory of the hard disk.
Step 7. Double-click on root.bat to start temp-rooting your Evo 3D. Follow the steps to finish this, if you have trouble, just watch the tutorial video in the beginning of this post.
Step 8. Next, open up a command prompt and type:
adb push misc_version /data/local/
adb shell chmod 755 /data/local/misc_version
adb shell /data/local/misc_version -s 1.10.651.2
adb reboot bootloader
fastboot getvar mainver
If you get back mainver: 1.10.651.2, you are good to go, go to the next step.
Step 9. Reboot your Evo 3D normally and connect to your computer. Set the USB mode to “Disk drive”.
Step 10. Copy the file RUU_Shooter_S_Sprint_WWE_2.08.651.3_Radio_0.97.10.0808_NV_SPCS_1.31_003_release_219445_signed.zip to the SD Card of your Evo 3D and rename it to PG86IMG.zip.
Step 11. Make sure you have “Hide extensions for known file types” turned off in Windows when you do Step 10. Sometimes you can add an extra “.zip” into the filename while renaming.
Step 12. Pull the battery out, and in, then boot into bootloader by holding down Volume Down and Power button together for 5 seconds.
Step 13. Wait about 5 minutes and you should get an option to choose Yes or No. Pull the battery cover out, connect an AC USB cable to your Evo 3D, take the battery out. Your Evo 3D should still be powered.
Step 14. Hit the Volume Up button (preferably with a small screw driver) and count 4 seconds. On 4 seconds, immediately pull the USB plug out.
Put the battery and back cover back on. Then hold down Volume Down button and plug in the micro-USB cable (from your computer) to your Evo 3D.
Under device manager, you should see something like “QHSUSB_DLOAD”. If you don’t see this (and see “Unknown device”), you will have to go back to Step 12 and keep doing it until you get this part right. Once you get it, it means you have put the Evo 3D is “brick mode” ready for HBOOT flashing.
Step 15. Open up 4 windows, get superuser access for all:
Browse to the directory where you copied the files.
Next do this for Window 1:
./emmc_recover –flash hboot_1.4.nb0 –device /dev/sdb13
Next do this for Window 2:
./emmc_recover –flash hboot_1.4.nb0 –device /dev/sdc13
Next do this for Window 3:
./emmc_recover –flash hboot_1.4.nb0 –device /dev/sde13
Next do this for Window 4:
./emmc_recover –flash hboot_1.4.nb0 –device /dev/sdf13
And hit enter 3 times for each window.
You can also open an additional window and type “tail -f /var/log/kern.log” so you can monitor the USB connections when you connect your Evo 3D to your Ubuntu computer later.
Step 16. Next, take the battery out of your Evo 3D and in, then WHILE HOLDING DOWN Volume Down button, plug your Evo 3D into your Ubuntu computer. You should see one of the Windows flashing the new HBOOT 1.40. If you fail, just try Step 16 again, it will work.
Step 17. If you got to Step 15 congratulations! You can simply reboot into your Evo 3D and use the Revolutionary root method to get it fully rooted again with S-OFF.
Credits – XDA
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