"Repairing disk errors. This might take over an hour to complete."

Hi,

We understand the issue you are facing and will assist you.

I suggest you to follow the steps provided below and check if it helps.

1. On a working PC, go to the Microsoft software download website and create Windows 10 installation media.
2. Insert the installation media you created, and then restart your PC.
3. After you boot your computer using Windows 10 DVD or System Repair Disc, a black screen appears with grey text "Press any key to boot from CD or DVD". Press any key.
4. Select the correct time and Keyboard type.
5. Click Repair your computer in the lower left corner.
6. Click on Troubleshooting, advanced option and then click Command prompt.
7. Type at the command prompt CHKDSK /P and press ENTER to scan the disk.
8. Then type CHKDSK C: /F /R and press ENTER to repair corrupt sectors, if there are any.
9. Once chkdsk completes, boot to the desktop and then check.

NOTE: The root drive has to be C: and the command may schedule a task at the system startup, if it does, then press Y to schedule a task and restart the computer to perform chkdsk.

Important: While performing chkdsk on the hard drive if any bad sectors are found on the hard drive when chkdsk tries to repair that sector if any data available on that might be lost. Please create a backup before performing a check disk.

Hope this helps. Keep us posted on the status for further assistance. 

Hi,

Thank you for your response.

A repair In-place upgrade will repair operating system files while preserving your personal files, settings and installed applications. On other hand, clean install will configure windows 10 by removing all your files, apps and settings. In simple a fresh windows 10 install.

We recommend you to take a Backup of personal and important files in both cases to avoid unwanted situations.

How to: perform a repair upgrade using the Windows 10 ISO file

You can refer this link to learn how to perform Clean Windows 10 Install. When you open the link, navigate to Using the media creation tool /> Performing a clean installation using USB or DVD for clean installation steps.

Note: If you’ve already successful activated Windows 10 on this PC, including if you upgraded by taking advantage of the free upgrade offer you won't need to enter a Windows 10 product key. You can skip the product key page by selecting the Skip button. Your PC will automatically activate later.

And also refer the link below and check if it helps.

How to: Do a clean install of Windows 10.

http://answers.microsoft.com/en-us/insider/wiki/insider_wintp-insider_install/how-to-do-a-clean-install-of-windows-10/aef0ae63-2117-41ee-a8ea-4a3181625b08

Keep us posted if you require further assistance.