Once again HTC has decided to make it super easy to unlock the bootloader of their upcoming flagship device! Keep in mind the current HTC stock method won't work on AT&T or Verizon variants, but will be good for the international T-mo and Sprint versions. The Verizon and AT&T versions will probably be hackable and already have developers who are interested and looking at ways to get those bootoloaders unlocked unofficially. Follow the quick guide below to unlock your HTC One M9 bootloader. 1. Install HTC usb drivers (the easiest way is to plug the phone into your PC's usb, Windows should find and install the drivers automagically. 2. Download the minimal Fastboot and ADB 3. Register account on HTC Developer Website, log in, click "unlock bootloader", then "get sarted" 4. power up M9 by holding volume down + power, from bootloader menu select "fastboot" with power button 5. Open command prompt from within folder containing Fastboot and ADB files on PC (open folder hold shift+right click then select open command window here 6. Type the command "fastboot oem get_identifier_token" without the quotes 7.This will output your unlock token which will be a long list of numbers. 8. Copy and paste the token at the htc dev website where it says "my device identifier token" click submit 9. HTC will email you the unlock_code.bin, place this into the fastboot and adb folder 10. Open a new command window from within the fastboot folder and type the command "fastboot flash unlocktoken Unlock_code.bin" without quotes 11.Confirm bootloader unlock on HTC screen by highlighting "yes" and selecting 12. Your phone will reboot and wipe data 13. Enjoy your unlocked bootloader!