I have two drives in my desktop, one is a 240GB SSD with Windows 8.1 Pro and and the other is a 120GB SSD with Windows 10 Pro. I currently have it set up to dual boot both OSes and it is working fine.

I want both Windows partitions on the same 240GB SSD so I can remove the 120GB SSD from the desktop. I do not want to have to reinstall Windows 10.

I am able to clone over the Windows 10 partition onto the Windows 8 drive using Macrium Reflect and it does so without any errors. I then use the EasyBCD tool to update the boot loader to point the Windows 10 entry to the new drive letter/partition that Windows 10 was clone to. I then remove the 120GB SSD. But then, when the system boots, and I select Windows 10 from the startup options, the Windows logo appears momentarily and then the screen goes black and Windows never loads. Oddly, on the black screen, I can move the mouse around, but clicking does nothing and keyboard commands do nothing. I tried getting into Windows 10 safe mode but that never loads either. Prior to the partition cloning, I made sure the 'fast startup' option is disabled. Even though Windows 10 fails to boot in this situation, Windows 8.1 continues to boot without any issue.

What is the easiest way that I can accomplish the dual boot setup on the 240GB SSD without reinstalling Windows 10?

  • Use the built-in tools to update BCD EasyBCD is prone to errors and will most definitely eventually cause irreparable damage causing you to reinstall your operating system – Ramhound Jul 30 '17 at 16:59
  • Ramhound, I tried modifying using bcdboot and got an error "BFSVC Error: Failed to open file F:\Windows\boot\PCAT\bootmgr for read! Error code 0x780. Failed to validate boot manager checksum. Failure when attempting to copy boot files" I am not sure what could be done to resolve that – Krondorian Jul 30 '17 at 17:17

The issue was hardware related. I would experience the same sort of black screen issue when removing my graphics card to try to revert it back to the on-board/integrated graphics. To get things working, I had to manually remove my graphics card drivers before doing the OS clone, such that it could revert back to the on-board graphics.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.