Check your BIOS settings and ensure the right device is first in the boot order
When you start up your computer, you can change the order of the devices connected to your PC in the BIOS menu.
To enter the BIOS menu, turn on your computer and watch the initial startup screen come up. This is the screen that has your PC manufacturer’s logo on it that appears before your operating system loads. On the startup screen, there will be a line of text telling you which key to press to enter the menu. The key varies from manufacturer to manufacturer, but it tends to be ESC, F1, F2, F8 or F10. You will only have a few seconds to press the button before your PC exits the startup screen.
The menu will vary between manufacturers, but by selecting the BIOS setup or device selection menu, you will be able to see which storage devices are connected to your computer. Make sure your computer’s internal hard disk drive is at the top of the list. If it already is and the “no bootable devices found” error persists, then something is wrong with your hard drive.
Reinstall Windows onto your PC’s hard drive
If you can’t fix the damage to your hard disk drive’s file system, but the drive seems physically healthy, consider reinstalling Windows and starting fresh.
Replace your hard drive and install a fresh version of your Windows operating system
If your hard disk drive is broken, you’ll need to buy a new one and install Windows onto it. None of your data will carry over from the old drive to the new one unless you have it backed up, and you’ll probably be spending the next few days tediously clearing out all the bloatware that comes with Windows and reinstalling all your favorite apps. But at least you’ll have a working PC again.
Check the cords to make sure your hard drive is securely connected
Again, this is a very rare and unlikely possibility, but it doesn’t hurt to check if this is causing a “no bootable devices found” error.