46

It's a security concern. The Android documentation doesn't provide a lot of elaboration, stating simply: The procedure must be confirmed on-screen, and deletes the user data for privacy reasons. However, the privacy concern is relatively straightforward to extrapolate. Once the bootloader is unlocked, the device can be flashed with unsigned images. This ...


30

A permanently unlocked boot loader (BL) on a Nexus device is a big security risk. It's only recommended for a pure developer phone. An insecure BL enables all sorts of fastboot commands that can be used for e.g. doing the following: Conduct a cold boot attack to recover the key for Android's full disk encryption Make a copy of the device E.g. by booting ...


16

Simply put, fastboot oem lock puts your bootloader into a mode that prevents you from overwriting your recovery image, without a subsequent fastboot oem unlock. This serves as a security precaution, primarily where the default recovery and firmware is installed. Because: The default recovery will only allow manufacturer/Google signed firmware to be ...


16

You'll need to use fastboot, which is provided in the CF-Auto-Root zip file, and also available standalone and packaged with lots of other software. It's part of the Android SDK Tools / Platform Tools, which can be installed on Windows, OSX, or Linux. Note: If you've installed a custom ROM or kernel on top of rooting, you'll want to flash the necessary ...


8

No, they're completely unrelated things. As you say, an unlocked device means it's not locked to a particular carrier: you can insert a different SIM card to change to a different carrier, and it will work. A locked device will not connect to another carrier if you change the SIM card. The bootloader is the first thing that runs when you turn the phone on: ...


7

A locked bootloader means that you won't be able to install software updates(or flash recoveries, ROMs) that hasn't been signed by the manufacturer/carrier. So the answer is "Yes, you can flash an unsigned ROM but it won't get loaded by the locked bootloader".


7

Qualcomm 9008 mode is for emergency repairs as a last resort - without it your phone could remain bricked under certain situations. However, in case of Xiaomi phones, even if you flashed the phone under this mode, the account lock (if there is any) will still be persistent and you won't be able to use any services related to it (i.e. Cloud). The original ...


6

Both /data and /sdcard are erased when you do fastboot oem unlock. So you lose not just files on the "SD card", but all installed applications and their internal settings and data. Yes, you can use adb backup to backup your data and then restore it later, either with adb restore or Titanium Backup Pro. However, when I did this (using adb restore), my MMS ...


5

The clue lies with the comment above But I just tried 'adb reboot bootloader', and it worked. which shows that adb is indeed recognizing the USB connection, but not in fast-boot mode which is where this answer comes in... Sounds like the udev rule for the fast-boot is absent! Do this: lsusb with the cable plugged in while the handset is in fast-boot mode. ...


5

From this xda thread by albundy2010 I have seen quite of few people screw up their devices by not knowing what they are doing. So I am making this thread to simply tell people not familiar with fastboot what they should and should not do. Fastboot oem unlock will unlock your bootloader and do a complete wipe of your device. As far as I know the only ...


4

No, the bootloader has no bearing on a SIM/network lock. The HTCdev site explicitly states this on the bootloader unlock page, in fact: Please note that unlocking your bootloader does not mean that you will be able to unlock the SIM lock. Unlocking your SIM lock is at the discretion of your operator/carrier and is not part of the bootloader ...


4

Well, when HTC leaves it up to us, it's up to us, so I kept playing with it. It turns out that the response I got is a generic response from fastboot: It does a piss-poor job of checking its arguments. That particular response, in effect, means, "invalid command arguments." Yes, I made a typographical error and this was the result. It didn't occur to me ...


4

XDA has reported that the bootloader is unlocked, and custom kernels have successfully been flashed to the SGSII.


4

Every Android phone has a bootloader that instructs the operating system kernel to boot normally. But you need to understand one thing here that as Android OS is an open source OS and is available on a variety of different hardware, every manufacturer has their own version of bootloader specific for the hardware present in its environment. (...) A bootloader ...


4

For Sony's specific case, it's because Sony has proprietary technology (X-Reality color management, BIONZ image processor, active noise cancelling techniques) for its stock camera that uses DRM security keys. When the bootloader is unlocked, the keys that reside on TA partition are removed, thus disabling the features. The use of proprietary technology also ...


3

Linux users: If you're stuck in "waiting for device", make sure you run fastboot as root, such as: $ sudo ./fastboot oem get_identifier_token ... (bootloader) (bootloader) < Please cut following message > (bootloader) <<<< Identifier Token Start >>>> (bootloader) C8750A7847621A009AAC7949E9B41A52 ... (...


3

It looks like your HBOOT needs to be upgraded to v1.02.0000 in order to use the HTCdev unlock method. The reason for this is that the Legend's bootloader did not originally ship with unlocking capabilities, so you need to upgrade to the version that added it. Unfortunately, the HTCdev site will give you an RUU to run, but since it's an .exe file it won't do ...


3

No. Unlocking the bootloader will do nothing for Google Play. Even rooting won't do anything by itself as far as phone compatibility goes. To get access to the apps without device restrictions, you must have a rooted phone. You then must edit the build.prop file to change your phone model to one that can install the app in question. See this android.se ...


3

The short answer is that it's different for each phone. There's no generic "install Android" procedure for two reasons: Unlike on a PC, where the Windows installer or Debian installer has drivers to access (almost) any PC hardware, in embedded devices each model needs a ROM image specific to that combination of hardware. The first part of any installation ...


3

If you're talking about sim unlock, it is possible to re-lock it back to the network as was often the case with old nokia dumb-phones. However, I have not seen this in practice with most phones now-a-days. Usually, once it is unlocked from the network, any sim card can go in place and use it. However, if you're talking about locking the boot-loader - then ...


3

It's not necessary. If your Xperia's bootloader is locked you can't install a custom kernel but you can install a custom ROM. I have MIUI with a stock 4.0.4 based kernel on my Xperia S.


3

Its a good question as to the motive in why they insist on this when getting manufacturers to make the handsets for carriers. The reason, I think, why carriers enforce "locked bootloaders", is really simplistic, in the event of handsets being stolen, and a tech-savvy thief can unlock it, it wipes the personal data in place thus ensuring that contacts etc ...


3

Unlocking Your Xperia Play Known issues It is currently not possible to unlock the boot loader for CDMA phones. Some customers with unlocked boot loaders have experienced problems when they are accepting over the air upgrades (FOTA - Firmware upgrade Over The Air). For customers that have unlocked the boot loader, please do not accept any over the air ...


3

Just relocking won't work, you need to restore the TA partition (which contains DRM keys for Bravia Engine) that you must have backed up before unlocking your bootloader.


3

As Firelord asked me to sum things up, here we go: First, you cannot do a backup using fastboot. Fastboot is like a one-way road: you can only use it to write partitions (either by flashing a corresponding image, or by wiping it) – but you cannot "pull" a partition. Which leaves ADB. Yes, it's possible via ADB – but it will require root. As Firelord ...


3

I cannot speak for other devices but Motorola Nexus 6 will show you a warning that userdata would be destroyed. The warning is shown both on the shell and on the device's screen. See screenshots: It is to be noted that the warning would show up only when OEM unlock setting is enabled under Developer options. If it is disabled and you attempt to re-lock the ...


3

I found this link after hours of searching and trying to unbrick my phone. Just type here https://imei24.com/ your IMEI number and it will show you all the info, hope it helps :) BR!


3

Toggling the setting in Developer Options does nothing but allow the bootloader to be unlocked, however actually unlocking the bootloader will wipe all data, just toggling the setting in Developer Options will not. It would be more proper to call the setting "OEM Unlocking is Allowed". Otherwise here might be a good place to start looking for more ...


2

I think your HBoot needs to be upgraded, and it sounds like perhaps you didn't run the RUU to do so. The HTCdev site notes that phones with an asterisk (*) next to them in the list must run an RUU before unlocking because the bootloader on the device did not originally ship with unlocking capabilities. So first you need to make sure your firmware is up to ...


2

Nexus Ones do not ship with 'S-OFF', they ship with a "locked" bootloader which then must be unlocked. You can actually use fastboot to unlock the bootloader, just run fastboot oem unlock on your PC using ADB (Android Device Bridge). MoDaCo has a post here with complete instructions and a multi-platform download of the needed tools.


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