You are in the wrong fastboot, fastbootd (with the d at the end!) is https://source.android.com/devices/bootloader/fastbootd , what you want is the "real" fastboot also called bootloader. Either select "Reboot to bootloader" in fastbootd or reboot the phone with fastboot reboot bootloader. Thx @ https://forum.fairphone.com/t/unknown-command-issue-w-fastbootd-solved/84559

This appears to be the answer to my question: Pixel 3 (blueline) immediately wipes the data partition upon unlocking the bootloader. It appears there is no way to boot it back into fastboot before erasure occurs.

Suddenly the problem got a solution. When the tablet was powered off (USB cable should be unplugged for that, otherwise TWRP powers the tablet always on), I held Volume Up and Volume Down and pressed the power button. In this case not the TWRP, but the standard Huawei downloader comes up, with an error message that system upgrade could not be performed (of course! I didn't put anything to the SD card). It had the only reboot button. After tapping this button the system boots normally. Because all the data was wiped out, it needed some time to initialize, but then worked normally. I had to configure Wi-Fi, and the system found an update from my current version ... to the same version, with the wording that it was a system restore: Restore system to latest official version. After downloading the system asked for a restart, rebooted and landed again in TWRP. I repeated the trick with three buttons, let the system to download the update, held Volume Up and Volume Down physical buttons and only then tapped on the "Instll now" screen button. It caused the stock recovery screen to appear. I tapped the reboot button there, and the update rolled out. After the update was complete, the system boots normally (except for the unlocked bootloader warning) and if volume+ button is held while powering on, the default recovery dialog appears. No traces of TWRP remained.

Samsung devices only have a placeholder Fastboot mode. It doesn't actually serve any purpose. Please use Download Mode instead.

If you haven't found out by now, You have been conned... In a big undercover action the FBI sold phones to criminals. The operation was a huge success. One of the consequences was that a lot of these pixel 4 were dumped for very attractive prices.... If the price is too good to be true...... As far as I know there's not much you can do. Best option is to buy a phone with a broken display and swap parts...

Oppo F11 has non-unlockable bootloader, fastboot is disabled intentionally. You can root with https://www.xda-developers.com/mediatek-su-rootkit-exploit method only, but carefully read instructions especially respect all warnings

https://forum.xda-developers.com/t/guide-fix-device-not-showing-up-in-fastboot-mode-windows-10.4194491/ So it turns out Windows doesn't like the OnePlus USB drivers because they are not signed. So you have to bypass it by disabling driver signing enforcement. install the OnePlus drivers that are included with your phone. --- they should show up as CD Drive: OnePlus Drivers when you just connect your phone to your computer This will create a directory like this... C:\Program Files (x86)\OnePlus USB Drivers, containing the USB driver In that folder there is a driver "" but both when installed from my phone, and a downloaded version, I ran into "The hash for the file is not present in the specified catalog file. The file is likely corrupt or the victim of tampering." So next we are going to disable signed drivers on windows. -----Select the "Start" button. -----Type "startup". -----Select "Change advanced startup settings". -----Select "Restart now" under the "Advanced startup" area. -----Select "Troubleshoot". -----Select "Advanced Options". -----Select "Startup Options". -----Select "Restart". -----A menu will appear where you can press "7" on your keyboard to choose "Disable driver signing enforcement". Now Device Driver Signing should be disabled, allowing you to install any driver you like in Windows 10 until you reboot. Boot your device into fastboot mode. This should cause it to show up in device manager as Android, with a yellow triangle In device manager (press windows + x to bring up a menu, then you can press m or select device manager for quick access) right click the android device -----Update driver -----Browse my computer -----Let me pick -----Have Disk -----Navigate to C:\Program Files (x86)\OnePlus USB Drivers -----Select OnePlus_android_winusb.inf and click okay -----OnePlus Android Bootloader Interface should be selected, and go ahead and install it.

SM-A405FN with Exynos chipset? I am not aware of any emergency download mode. Let battery drain for few days. Press and keep holding both Volume buttons when plug in charger. If you still can't reach download mode, buy JIG dongle (your last hope)

assume you are running windows, I will give you short instructions how to read data off dead device in EDL mode with QFIL disconnect battery from phone mainboard, press vol up + vol dn and connect usb-cable you should see Qualcomm HS-USB QD-Loader 9008 in windows device manager Ports (COM & LPT) section install Qualcomm HS-USB QD-Loader 9008 drivers download stock rom and open QFIL now follow the steps in this https://forum.xda-developers.com/showthread.php?t=4100897 , but instead devinfo you are interested in partition userdata Select "Flat build" Select your firehose (prog_emmc_firehose_8909.mbn) Select tools, partition manager Click ok Right click userdata and click on "Manage Partition data" Click on "Read Data" Check the logs on the main window, it will show you where it will be saved (Most frequently in the Appdata/Roaming/Qualcomm folder) Copy the file we read to somewhere like the desktop and make a backup in case it does not work. now you got the raw dump of your userdata partition. you can mount it with DiskInternals Linux Reader and recover your files from media folder (as long as phone is not encrypted) If your phone is encrypted you can swap mainboard with working device if eMMC flash storage chip is located on the mainboard itself

This is all happen in OEM bootloader (proprietary) before android is started. This screen is displayed before splash screen only in yellow/orange/red state

this device is not bootloader locked

The combination of encryption, PIN lock, and having ADB turned off should protect your data pretty well. It could still be compromised if someone finds a security flaw that can be exploited through the network or the MTP USB connection, but that risk exists in any case. However, with your bootloader unlocked, someone could take your phone, flash a malicious ROM that contains keystroke loggers or something, and then return the phone to you and wait for you to type your PIN or decryption password. It'd be better to keep the bootloader locked whenever you don't actually need to flash things via fastboot. You can use BootUnlocker to lock and unlock the bootloader from within the running Android system. Unlike fastboot oem unlock, this doesn't wipe your data when you unlock.

If you can find an original stock ROM for your device (I assume your device is not rooted etc.), or any fitting custom ROM (in case it is rooted etc.), you could factory-reset your device and then flash that ROM. See Where can I find stock or custom ROMs for my Android device? for available ROM sources.

I was able to solve this problem by draining the tabs battery completely. After a day I was able to turn it on using the power button today while charging.

It was enough flashing the device with RUU_Buzz_Froyo_HTC_WWE_2.22.405.1_Radio_13.55.55.24H_3.35.20.10_release_160191_signed.exe

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. Typical output should be one similar to this: Bus 001 Device 012: ID 18d1:d00d Google Inc. ^^^^ ^^^^ The numbers identifier 18d1:d00d corresponds to idVendor : idProduct respectively. Make note of it, and check your udev rules found in /etc/udev/rules.d/51-android-rules. (Mileage will vary slightly with differing Linux distributions!) If you do not have this file, then its recommended to create one using root, there may be a few rules that need to be added depending on the mode of the handset, i.e. normal, recovery and boot-loader modes. Here's an example of mine, that has differing values respectively when handset is in one of these modes. Take this as a template and change the numbers as shown that matches up with idVendor and idProduct respectively to suit your make/model of handset. SUBSYSTEMS=="usb", ATTRS{idVendor}=="19d2", ATTRS{idProduct}=="1354", MODE="0666" GROUP="androiddev", SYMLINK+="android%n" SUBSYSTEMS=="usb", ATTRS{idVendor}=="19d2", ATTRS{idProduct}=="1350", MODE="0666" GROUP="androiddev", SYMLINK+="android%n" SUBSYSTEMS=="usb", ATTRS{idVendor}=="19d2", ATTRS{idProduct}=="1351", MODE="0666" GROUP="androiddev", SYMLINK+="android%n" SUBSYSTEMS=="usb", ATTRS{idVendor}=="18d1", ATTRS{idProduct}=="d00d", MODE="0666" GROUP="androiddev", SYMLINK+="android%n" The user id is added to the androiddev group, which was created on previous occasion, in that way I do not have to sudo at all! To create a group, using root groupadd androiddev, this creates a group, then to add your linux's user id to that group... usermod -a -G androiddev your_user_id; replace your_user_id with your own user id used for logging in). Then when in fast-boot mode, the fastboot binary should work (bonus! without the necessitating for sudo either!)

S-OFF is mainly found in HTC devices, and is a separate security mechanism whereas the /system directory cannot be mounted RW across boots. It also restricts other features. If S-OFF is enabled, fastboot can't be disabled, as fastboot would have to be enabled to turn S off. As such, fastboot would most likely be enabled, unless it was re-locked in some way (which would in turn lock S to ON).

The boot-loader code is stored within the /boot partition. Majority of Android handsets uses the Qualcomm's Boot Loader, called LK (Little Kernel), barring Samsung, which uses their own form of boot-code. LK has the following: Variety of nand devices for bootup USB driver to enable upgrading images over usb during development Keypad driver to enable developers enter ‘fastboot’ mode for image upgrades Display driver for debugging and splash screen Enable Android recovery image and image upgrades This applies to only, Qualcomm chipsets hence the exemption of Samsung based handsets There is a website blog that cites this from source The actual source code, if anyone is curious enough, can be found on CodeAurora site. This is known as CAF, in which a lot of Qualcomm specific code for kernels can be found in. As a side-note: Google releases source to AOSP, CAF, pulls from them, modifies it to make it fit within Qualcomm chipsets, then the Manufacturers pull those down and add their own bits, it is that for the reason there's, AOSP, CAF and CyanogenMod that are the main three flavours of Android. The actual source code to the boot-loader can be found on CAF's git repository, and has not changed much, it can also be found in CyanogenMod's source, specifically in, /bootable/bootloader also.

Root One X. Official bootloader unlock and unofficial unlock. Found all of these via Google. You can always search online for these kind of questions. And this question is likely to be closed down.

Try to flash another firmware. Find it here , it has flashing guides too. Follow the instructions strictly Tell us about your success or your failure