|Technical answer: Each little area on the disk that can store data is called a sector. Hard drives come with some "extra" sectors so that when some "go bad" the extras can replace them. Your hard drive is running out of these extra sectors. That means when future sectors go bad, there will be nothing to replace them, and you will start seeing problems with read/writing data.|
So, as suggested above, backup all of your data first, then get a new hard drive. Backing up is your priority, but after that you can do us a program like Easus ToDo Backup, Partition magic, Acronis True Image, etc. to "clone" your drive to a new one. Then it's just a matter of physically swapping the drives, and you will be right back in business. No need to reinstall Windows or anything.
PS: It is best that you don't do ANYTHING else on the computer until you have backed up your data. Turn it off, and leave it off until you are completely ready to backup.
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