If it happens for the first time, shut down your PC/Laptop AND REBOOT, it may fix it's self. This example is for windows 10, but if you are having issues with older Windows versions you'll need the CD/Disc or iso for that version.
Step 1: I would suggest you to download an
ISO image of Windows 10 and try to install again using the Media Creation tool.
https://www.microsoft.com/en-us/software-download/windows10 Installation Media tool:https://windows.microsoft.com/en-us/windows-10/media-creation-tool-install Once the bootable media is created, follow next step:
Step 2: Perform
Start up Repair.
Follow the steps mentioned below to perform
Start up Repair:
a.
Insert the installation
DVD or
USB and boot Windows 10 from it.
b. Select “
Troubleshooting” from the first Window and then select “
Advance Options”.
c. Then select “
Automatic Repair” from “
Advanced options” window.
This will help you to boot into your Operating system again.
In many cases this issue occurs due to a corrupt boot sector on your hard drive.
If this does not work boot your computer in the Bios mode and check to see if your Hard drive is available or detected!