This issue may occur due to corrupt or missing Windows startup files.
I would suggest you to try starting your computer in safe mode and check if it helps. Please follow these steps:
a. If you don’t have installation media, use the power button to restart your computer three times. This will start the Windows recovery environment.
b. In the Windows recovery environment, on the "Choose an option" screen, click "Troubleshoot".
c. Click "Advanced options" and then click "Startup Settings".
d. Click "Restart" and press either "4" or "F4" key to select safe mode.
If computer starts in safe mode, then perform clean boot.
Refer this article:
https://support.microsoft.com/en-us/kb/929135
Clean boot is performed to start Windows by using a minimal set of drivers and startup programs. This helps eliminate software conflicts that occur when you install a program or an update or when you run a program.
Note: After you have finished troubleshooting, follow these steps from section “How to reset the computer to start as usual after clean boot troubleshooting” to reset the computer to start as usual.
If computer does not boot to safe mode, then try running startup repair from Windows recovery environment and check. Please follow these steps:
a. Do one of the following, depending on whether you have installation media (such as a DVD or USB flash drive):
- If you have installation media for Windows, start your computer from the installation media. Insert the DVD or USB flash drive and restart your computer. If you see a message asking you to "Press any key to boot from DVD", do so. If you don’t see the message, you might need to change the boot order in your computer's BIOS settings so that it first starts from the DVD or USB. When you see the "Install Windows" page, click "Repair your computer" to start the Windows recovery environment.
- If you don’t have installation media, use the power button to restart your computer three times. This will start the Windows recovery environment.
b. In the Windows recovery environment, on the "Choose an option" screen, click "Troubleshoot".
c. Click "Advanced options" and then click "Startup Repair".
You may download the upgrade files, create an installation media and then upgrade to Windows 10.
Please refer this article:
https://forums.windowscentral.com/e...Fsoftware-download%2Fwindows10&token=CTG8GACx