Last Updated: March 22nd, 2011

Update: Bootloader and recovery are both locked and signed. See new screenshot.

Update #2: The device has been rooted, and its bootloader has been unlocked!

Some of our good friends over at AndIRC (most thanks going to scotty2 for discovering it, and Trident for being the guinea pig) have discovered a bit of troubling information regarding the HTC Thunderbolt: its bootloader and recovery are locked. What does that mean, exactly? No custom ROMs - for now. Some enterprising hackers successfully flashed a custom recovery image onto a T-bolt, but lo and behold, upon entering the bootloader, no recovery boot option was to be found once the flash had been completed.


Similar security measures have been put in place on Motorola phones. The basic gist is this: if you somehow manage to flash a custom recovery image to your phone, a failsafe (known as a signature check) will kick in on boot-up and examine the "signature" of the recovery image loaded onto your phone. If the known "good" signature (HTC's key, basically) stored on the phone's read-only-memory doesn't match the signature of the recovery image, the phone's bootloader won't allow you to access recovery.


Image credit: Trident

This, in turn, means you can't go flashing ZIPs and custom ROMs to your phone willy-nilly, which is what the manufacturers want to keep you from doing. Of course, it's only a matter of time until a way around this obstacle is discovered - and we have it on good authority that scotty2 and the AndIRC team have a surprise in store for us very soon. So, hold onto your butts.

AndIRC, scotty2, Trident

David Ruddock
David's phone is whatever is currently sitting on his desk. He is an avid writer, and enjoys playing devil's advocate in editorials, and reviewing the latest phones and gadgets. He also doesn't usually write such boring sentences.

  • Kenneth P

    Nooooo!!! not HTC tooo!! HTC was my ace in the hole! It must be a Verizon thing

  • bworth

    I just bought a Thunderbolt. I was planning to root and flash it. Might just have to go back to the iPhone.

    • Eric

      whle this does suck, how forgoing to the iPhone, an even more locked doqn device solve it

  • HTC Suxit

    So the Thunderbolt bites it... Bionic is going to bite it... COMON manufacturers... Get with the times!

  • Trae

    This wreaks of Verizon. First unwanted bloatware, and now a locked bootloader. What's next VZW? With all the lockdowns you've essentially taken away the freedom of Android. If I want this kind of handholding and this brand of "cellular prison" I would have purchased an Iphone in February...

  • Josh H.

    if the EVO 3D is locked I'm going to be pissed!

  • i’vebeenonarealbigboat

    this means nothing. recovery and s-off will still happen, its like this with all htc phones. incredible, g2 etc. just a matter of time

  • jcase

    Don't stress quite yet.

  • http://www.psycho.ziggy471.com JerrryLange

    will donate to the person who unlocks this phone. this NEEDS to be done. I love this phone. what am i going to go back to? small screened incredible?

  • okcnyyfan

    I dont think its the manufacturers, I think its the carriers. The manufacturer has no stake in the phone once it's sold, outside of warranty coverage. It's the carriers who dont want you to access the extra features (wifi hotspot, tethering) so they can charge you for those. The manufacturer locks the bootloader so they can sell it to the carrier.

    • eleazar

      I think warranty coverage is the largest stake that can be had in a phone, especially when it comes to flashing custom roms and rooting. If locking down the bootloader saves them from replacing a few thousand phones that got bricked by idiots that can't follow directions, they are going to do it.

      I'm of the mindset that they should offer unlocking of the bootloader as a feature that voids your software warranty. They should still cover any hardware defects despite unlock/lock status.

  • http://pornhub.com C0nc3|2N3D_C171z3N

    Thanks HTC. You are in for it now. When this gets fully unlocked I hope the first print_id script for the recovery update is FUCK YOU.

    Assholes. Nice attempt.

    1 Sandpaper Condom coming up.

  • Alvin

    G2 had this problem and they defeated it so don't get upset just yet. Be patient. If they can't do it, then we have a big problem.