How to fix inaccessible boot drive (0x78)

Question

4 month old computer will not boot up windows. Says inaccessible boot drive (0x78).

Answer 1

Start your PC, just as Windows attempts to load (spinning dots), press and hold Power Button for 5 - 10 seconds to perform a Hard Shut Down

Do this twice

On the third start Windows will boot into the Recovery Environment and from there you can access System Repair, Safe Mode, Command Prompt... etc.

Please try each option one at a time, then see if Windows will boot up correctly.

.

Go to Troubleshoot - Advanced Option - Startup Repair

See if Windows startup can repair itself

.

Go to Troubleshoot - Advanced Option - Command Prompt.

Run this command and press Enter.

bootrec /FixMbr

Run this command and press Enter.

bootrec /FixBoot

Run this command and press Enter.

bootrec /ScanOs

Run this command and press Enter.

bootrec /RebuildBcd

Then reboot your PC.

Answer 2

To troubleshoot the "Inaccessible Boot Drive (0x78)" error on your Windows computer, you can follow these steps:

1. Check Hardware Connections: Ensure that the hard drive is properly connected. If it's a desktop, check the SATA cables; if it's a laptop, ensure the drive is securely seated.
2. Boot into Windows Recovery Environment (WinRE): You can do this by using a Windows installation media. Start your computer with the installation media, select Repair your computer, and then choose Troubleshoot > Advanced options > Command Prompt.
3. Run Diskpart: In the Command Prompt, type diskpart and then list disk to verify that your hard drive is detected. If it is not listed, there may be a hardware issue.
4. Check Boot Configuration: Run bcdedit to check the Boot Configuration Data (BCD). Ensure that the entries point to the correct device and boot loader file.
5. Rebuild Boot Files: If the BCD is corrupted, you can use the bcdboot command to recreate the boot files. For example:

      bcdboot D:\windows /s R: /f ALL
   

   Replace D: with your OS drive and R: with your system drive.
6. Check for Corrupted Drivers: If the issue persists, it might be due to corrupted drivers. In WinRE, you can load the registry and check for any third-party drivers under HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class. Remove any non-Microsoft drivers found there.
7. Restore from Backup: If you have a backup of your system, consider restoring it to a previous state when it was functioning correctly.
8. Check for Windows Updates: Sometimes, pending updates can cause boot issues. You can check for pending updates using the DISM command in the Command Prompt:

      DISM /image:C:\ /get-packages
   

   If there are pending updates, you can uninstall them to see if it resolves the issue.

If these steps do not resolve the issue, it may be necessary to consult with a professional or consider hardware diagnostics.