If you are using Windows then chkdsk can identify the bad sectors and mark them as bad.
Bad sectors are physicaly bad, which usually means that they are physically damaged, so they can not be repaired.
There are many third party tool available which can fix logically bad sectors. However, if your harddisk has a physical bad sector. I would suggest you to get in touch with vendor who i i think will replace if its under warranty.
One tool that I have used in past. Link for same is mentioned bleow
I will help you detect and fix bad sectors. Please backup your data before following any operation on your hard drive.
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If you are using Windows Operating System, you can use the Check-disk utility which is a built in feature of any latest version of Windows Operating System. You can choose to automatically scan and repair bad sectors so that you don’t have to manually repair those errors.