I got my MacBook Air secondhand last October and have used it fine since, but just recently I turned it on and it’s asking me to enter a password to unlock the disk “Macintosh HD” then when I do it restarts the Mac, but just pops up with the same screen again every time. I can go to the Mac logo and open ‘choose startup disk’ but there is only one option there and I get the same result when I restart.
MacBook Air 13″
The APFS file system may be corrupt, or macOS may be damaged, or you may have a software/configuration issue, or you may have a hardware issue. With these newer Macs & macOS it can be very difficult to figure out or even resolve it.
What is the exact model of your MBAir and version of macOS used? You can get the exact model by entering the system serial number on the check coverage page here (do NOT post your serial number on the forum as it is considered personal information):
Check Your Service and Support Coverage - Apple Support
Disconnect all external devices from the laptop in case one of them is causing a problem.
Try booting into Safe Mode to see if you can get to the Desktop. Make sure to hold the Shift key again as you use the Trackpad to click the Unlock/Submit button if you are prompted for the Filevault password during boot (necessary for an Intel Mac, not sure about an M-series Mac). If this works, then you most likely have some third party software causing a problem, or perhaps even a file system issue or temp/cache file issue (the latter two items will be corrected automatically by Safe Mode, so rebooting normally may work if one of the latter two were the cause).
You can try booting into Recovery Mode and running Disk Utility First Aid on the hidden Container. Within Disk Utility you will need to click "View" and select "Show All Devices" before the hidden Container appears on the left pane of Disk Utility. Even if First Aid says everything is "Ok", click "Show Details" and scroll back through the report to see if any unfixed errors are listed. If there are errors, then run First Aid again until they are gone. If after several attempts they errors remain, then you will need to perform a clean install of macOS by first erasing the disk followed by reinstalling macOS & restoring from a backup.
If First Aid reports no file system issues, then launch the Terminal app from the Utilities menu and issue the following command to clear the NVRAM (safe for both Intel & M-series Macs):
nvram -c
You may see a message or two about not having permission to delete some items such as the Computer Name.....this is fine. Reboot the computer to see what happens.
Try running the Apple Diagnostics to see if any hardware issues are detected.
The APFS file system may be corrupt, or macOS may be damaged, or you may have a software/configuration issue, or you may have a hardware issue. With these newer Macs & macOS it can be very difficult to figure out or even resolve it.
What is the exact model of your MBAir and version of macOS used? You can get the exact model by entering the system serial number on the check coverage page here (do NOT post your serial number on the forum as it is considered personal information):
Check Your Service and Support Coverage - Apple Support
Disconnect all external devices from the laptop in case one of them is causing a problem.
Try booting into Safe Mode to see if you can get to the Desktop. Make sure to hold the Shift key again as you use the Trackpad to click the Unlock/Submit button if you are prompted for the Filevault password during boot (necessary for an Intel Mac, not sure about an M-series Mac). If this works, then you most likely have some third party software causing a problem, or perhaps even a file system issue or temp/cache file issue (the latter two items will be corrected automatically by Safe Mode, so rebooting normally may work if one of the latter two were the cause).
You can try booting into Recovery Mode and running Disk Utility First Aid on the hidden Container. Within Disk Utility you will need to click "View" and select "Show All Devices" before the hidden Container appears on the left pane of Disk Utility. Even if First Aid says everything is "Ok", click "Show Details" and scroll back through the report to see if any unfixed errors are listed. If there are errors, then run First Aid again until they are gone. If after several attempts they errors remain, then you will need to perform a clean install of macOS by first erasing the disk followed by reinstalling macOS & restoring from a backup.
If First Aid reports no file system issues, then launch the Terminal app from the Utilities menu and issue the following command to clear the NVRAM (safe for both Intel & M-series Macs):
nvram -c
You may see a message or two about not having permission to delete some items such as the Computer Name.....this is fine. Reboot the computer to see what happens.
Try running the Apple Diagnostics to see if any hardware issues are detected.
choose startup disk loop