What is BL lock? BL lock is the abbreviation of BootLoader. It is a small program running before the operation of the operating system core. In order to prevent the third-party app from hacking into the three-party system in batch, and modify the system configuration file which might cause user information leakage, Mi phone has added the BL lock. When the reinstallation or ROOT is required, the BL lock needs to be unlocked before the operation can continue.
Q1:How to unlock the BL Lock? Currently all users have unlock rights, and there’s no need to apply in MIUI forum. 1). Enter the forum for the unlock tool: http://en.miui.com/unlock/ 2). Log in to the Mi account that already has unlock authority in the device that needs to be unlocked, and pair the account and device in "Settings -> Developer Options -> Device Unlock Status "(this option is not available until after V8.1). 3). After logging in, manually enter fastboot mode (Shuts down the phone, and press the volume button while boot). 4). In the Xiaomi unlock tool on the computer, log into Xiaomi account with unlock authority on the phone, and connect to the phone through USB. 5). Tap "unlock ", the unlock will be completed in about 10 seconds.
Q2:What preconditions are required for unlocking and what needs to be noted? The unlocking first requires a valid SIM card, and each SIM card can pair 2 machines within three months. In addition, to unlock need to select “Bind account and device'” from the phone developer option, and wait for the pairing. The interval between unlocking two devices under the same account needs to be longer than 30 days.
Q3:When unlocked, how long does the account need to be paired? All the phones bound after November 22, 2018 need to wait for 15 days. For security reasons, to prevent batch reinstallation, for some users after the pairing the waiting time is adjusted to 60 days. Note: 1). The 15-day period after BL lock pairing means the phoned needs to be connected to the network for 15 days, not a 15-day waiting period. 2). If the user's mobile phone logs in with another Xiaomi account during the process, the unlock time needs to be recalculated.
Q4:Does unlocking clear user data? In order to prevent the user's privacy from being stolen, Mi 6, Mi Mix 2, Mi Note 3 and the subsequent models will clear user data when successfully unlocked, whereas other models will not. In addition, if the user's phone has enabled full encryption, unlocking will also clear all data, it is recommended that to back up before unlocking.
Q5:How to re-lock after unlock? The unlocked phone can be re-locked after reinstall the official MIUI package again. Select the reinstalltation script: delete and lock, (flash_all_lock.bat).
Q6:How do I know if my phone is unlocked? 1). Enter Setup>>Developer Options>>Device unlocking state, and unlocked device will display as “unlocked”. 2). When the phone is turned on, the startup interface will display "unlocked"
Q7:Common faults and solutions when unlock: When prompts "The current unlocked account does not correspond to the registered account in the phone ": 1) .Ensure that the mobile phone account and account of the unlock tool are consistent. 2). If the account are consistent, but the problem persists, for stable version users, it is suggested that they wait for 5 to 7 days after the first unlock verification failure, and the back end will make adjustments to the situation. After 5-7 days they can unlock the phone, and no other operations are needed. 3). For the development version users, it is recommended to pair the account and the device, and generally within two days they can try to unlock again. The pairing steps are as follows: settings > more settings > developer options > device unlock status > click "pair account and device ".
Q8:The Unlock Tool prompts account query abnormal 1). Whether accounts on the the mobile phone and the computer are consistent. 2). Whether selected the “Account pairing Device” in the developer option and has waited for corresponding time. 3). If the above are confirmed to be all right, It is recommended that use the mobile phone that logs into this account and turn off Account protection. Try: Settings - Xiaomi account - login and security - account protection (only part of the earlier system version has this option). If need to unlocked the phone, after reinstalling the machine and want to turn on the Root or reinstall the phone again, it still prompts the phone is unlocked The default script for the tool MIflash is "Delete all and lock". If the user does not modify the script, the default script will be locked again after the reinstallation. It is recommended that check whether the lock is caused by the reason. Unlock Bootloader process Q&A：
Q1：How to do if the unlock tool prompts "Account and device inconsistent"? A：This is because accounts and equipment validation failed in the process of unlock. Solution: first upgrade the phone to the latest stable version, or update from the stable version to the latest development version, log in the same account on the device and unlock tool, and enter the "Settings - > Developer Options - > Mi Unlock status" to bind the accounts and equipment.
Q2：How to do if the unlock tool prompts "Unable to access mobile phone information"? A： In this case, the device driver on the computer is not properly installed. It is recommended that try to re-plug the USB cable, change USB port or change USB cable to wait for the computer to slowly install the driver, or install the driver in the drive installation module in the upper right corner of the tool.
Q3： Unlocking failed and prompts that "the binding time between the account and the device is too short, please unlock after XXX hours" A： New models on sale generally need to wait, and users with low security score need to wait. The waiting time is currently over 7 days. If the number of unlocked phones exceeds 2 this year, the waiting time will increase accordingly.
Q4：Unlocking failure prompts that "this account has reached the maximum number of unlocking times this month" A： A Xiaomi account is limited to unlocking one device per month.
Q5： Failure of unlocking indicates that "the cumulative unlocking times of this account this year have reached the upper limit" A：One Xiaomi account is limited to unlocking 4 different devices per year.
Q6：Unlocking failure prompts "Insufficient account privileges or limited account" A： There is security risk of the account. It is impossible to solve the lock operation. It is suggested to change the account.
Q7：Unlocking failure prompts "unknown error -1" A：The network is abnormal. Please change the time period or the network to unlock.
