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I thin I have error on the hard disk.
How do I check it ? I have a macbook.

There are several ways.

The recommanded way is Repair Your Disk in macOS Recovery,
Restart or turn on your Mac, then immediately press and hold Cmd + R. Release the keys when your Mac displays anything on the screen.
Once you’re in macOS Recovery, launch Disk Utility and proceed to run First Aid.


You can also use fsck in Single User Mode
To boot into Single-User mode, Cmd + S when your computer boots.
(On some Macs you can open it in macOS Recovery and choose Utilities > Terminal)
Open Terminal and type (f means that it’ll force the utility to check the drive file system, and y means it’ll automatically confirm the actions of fsck command.)