The chances of getting an unlocked bootloader on the AT&T version of the HTC One X looked pretty grim a few weeks ago when HTC hinted that AT&T was the reason for keeping the bootloader of this phone locked down. Many AT&T Android enthusiasts were in an uproar and frantically trying to find a way to unlock AT&T's latest smartphone.
Thankfully XDA member grankin01 is here to save the day. He found a pretty ingenious way of unlocking the bootloader without exploiting any security vulnerabilities. All you have to do is trick your AT&T HTC One X into thinking it's from the land of lumberjacks and hockey sticks, Canada. You see, the Rogers (Canadian carrier) version of the HTC One X is completely unlockedable via htcdev.com.
Even though it sounds so simple, the actual method may be a bit daunting for some. But, if you're brave enough and willing we've provided the instructions below. Good luck.
Alright, once again, you do this at your own risk!
You need ADB and an understanding of how to use it and have a rooted device (although I didn't test this). You will also need a hex editor like HxD.
BACK UP YOUR DATA BEFORE DOING THIS!!!! WHEN HTCDEV UNLOCKS YOUR DEVICE YOU MUST START FROM SCRATCH!!!
1. Fire up your command prompt and go to the directory that you have ADB installed to. Type "adb shell" and hit enter.
2. Type "su" and hit enter. You now have root privileges.
3. Next type "dd if=/dev/block/mmcblk0p4 of=/sdcard/mmcblk0p4" and hit enter. This will dump the partition to your sdcard.
4. Next type "exit", hit enter, type "exit", and hit enter again. This should take you back to a command prompt for your computer.
5. type "adb pull /sdcard/mmcblk0p4" and hit enter.
6. Open the file (mmcblk0p4) with your hex editor.
7. Look for offset 00000210 and you should see CWS_001 with your IMEI number attached to it.
8. Change CWS_001 to ROGER001 and save the file as mmcblk0p4MOD.
9. Now go back to your command prompt and type "adb push mmcblk0p4MOD /sdcard/mmcblk0p4MOD" and hit enter.
10. Type "adb shell" and hit enter then type "su" and hit enter again. This will put you back into the android shell and give you root privileges.
11. Type "dd if=/sdcard/mmcblk0p4MOD of=/dev/block/mmcblk0p4" and hit enter. To test if it worked restart the phone into fastboot (type "adb reboot bootloader" and hit enter) and once the bootloader screen comes up type "fastboot oem readcid" and hit enter. It should read "ROGER001".
12. Next type "fastboot oem get_identifier_token" and hit enter. Leave that up on your screen and go to HTCdev.com. Follow the instructions from there.