Last Updated on Jul 31, 2021Know why your mac saying Macintosh HD-Data” Can’t Be Unlocked on startup and After Reinstall or Upgrade to MacOS Version to latest one. Now a Days macOS Big Sur users are getting these error popup messages on the screen every time when turning on and logging in to Mac or MacBook. Most people affected by this error due to Beta and Public macOS installed [macOS Big Sur] on separate Partition on the same Mac, MacBook Drive. The Warning message on the screen is “The Disk “Macintosh HD – Data” can’t be unlocked. A problem was detected with the disk that prevents it from being unlocked.
What Does Affect on Mac Behind this Problem?We will fix the problem in two ways, First is Normal mode and the second is in recovery mode,
1). Fix macOS Partition on Mac DiskThis Error or Warning message is saying that your Mac is in a problem to open a disk partition, So your mac has too many or more than one Disk Partition for Install MacOS. and You have to Re-install macOS On another Partition. In this can you have to identify active or Needed partition then delete unused another Partition.
- Open Finder on Mac > From Top Mac Menu Go > Utility.
- Find “Disk Utility” and Open it.
2) Backup Mac DataBackup of your Mac Data must be a critical step because this problem we can’t figure out without deleting the Volume partition and Re-installation of your Mac. So you will lose the data. I recommend taking a Time Machine backup to External Drive.
- Go to the Apple Logo > System Preferences > Time Machine > Select Drive and Start Time machine backup.
3). First Aid – Repair the Drive From Disk UtilityRepair the Volume option delete the internal system error and repair itself. Sometimes, it’s time-consuming that depends on the Data size saved on your Mac’s drive.
- Open Disk Utility Window > Now, Click on View > “Show Sidebar” and “Show All Devices” on Mac.
- Select the Volume from sidebar > and Click on the First aid option to start the repairing process.
4). Erase Volume PartitionBefore starting the Erasing process you have to check and identify which Volume Partition Data folder is in use. Because you have to Erase the Duplicate Machintosh HD Data Volume only.
- Open “Finder” on Mac > From top Mac menu Click on “Go” > “Utilities” > and Open “Disk Utility“.
- Now, Click on View > “Show Sidebar” and “Show All Devices” on Mac.
- Find Using MacOS Version installed on your Mac’s Partition. Select Unused or Duplicated Volume partition, then Select Erase option from top options on a window.
Go Through macOS Recovery and Fix the issuesEnter your Mac into MacOS Recovery, Perform all the repair, Reinstall or Erase the Duplicate drive from the macOS Recovery window. Run First Aid:- if you are in recovery mode then you will see the macOS Utility screen, Select “Disk Utility” Option > “Continue“. Select the volume from the sidebar and run first aid. or To Erase the Drive, Select the volume from the sidebar from Disk Utility and Select Erase from the top of the window. In the same way, we can Erase Apple Drive completely using Disk Utility to remove all unused Volumes and Partition from mac SSD or HDD internal drive.
- Intel Mac: Shut Down your Mac and Wait for 20 seconds. Now, Press and Hold the Power button [Touch ID] button until you see the Startup volume drive or Options > Enter your Mac password and See macOS Recovery Window > See and Click on Reinstall macOS.
- M1 Mac: Then Re-install new macOS on Your Mac. Start your Mac > Press Command + R key to See macOS Recovery Window > Select install macOS, Your Mac will download lateset macOS from the internet and install.