The most probable causes of the issue are that either the user might have pulled out the external drive directly without using the “Safely remove hardware” option, or when the drive was in use or general corruption of the content.
There was a problem repairing this drive, Windows was unable to repair the drive
If you face this issue, the first thing you could do is to safely remove the hardware, restart your PC and then connect your USB and see if it works. If not, then follow these two suggestions: Before you begin, you may want to create a system restore point or backup your data to an external drive.
1] Run CHKDSK from the command line
While some users have reported the error after the CHKDSK scan itself, others have shared the message while repairing a drive using in-built tools. In case you are among the latter, you could try running a CHKDSK scan before anything else. The scan checks the hard drive for bad sectors and repairs them if possible. You need to Run CHKDSK from the command line. So open CMD and execute the following command: Here ‘x’ is the Disk Letter.
2] Restart the system in clean boot state and run the scan
At times, a program could be conflicting with the scanning process. Since many processes run in the background, it would be difficult to conclude which one of them is causing the problem. Restarting the system in Clean Boot State could help with the same. You could perform your scan after that. Lastly, make sure not to remove a hard drive when it is in use. When file copy or usage is in progress, part of the drive is locked, and if the power ends abruptly, it results in corruption. We hope these tips helped you to fix Windows was unable to repair the drive.
3] Use a 3rd-party tool to check the disk
You can use a 3rd-party tool to check the disk. The fact that this error appears on your screen signifies that the disk is unable to repair itself automatically. Ideally, both the disk and the Windows operating system try to detect the error. If Windows displays the error, it in itself means that the disk is probably failing. However, a few interfering programs could also cause the issue as well. To understand what is affecting you, you could use a 3rd party freeware. Hope something here helps you. Related read: Windows detected a hard disk problem.