How to fix boot for windows 7 when bcdboot says "failure to copy boot"

Epicity said:

Yes, I was actually in the the system recovery mode when I tried that

Bcdboot does not depend on system recovery mode. Give it a shot running Windows.

Regards, VZ

Ok, I did end up fixing it but through some roundabout unintentional means.

I accidentally reset my boot using easyBCD which meant I had no boot menu at all. So using my win10 usb, the bcdboot actually managed to repair my 3 windows but only Win7 worked and i could only boot it from the drive that didn't run it, odd but it worked.

And once I got into win7 it was easy sailing with easy bcd as it worked fine there. Dunno why easybcd works in win7 to attach win 10 and not vice versa.

Please don't use external links to post images. Use the paper clip on the Quick Reply window. Browse to the saved image - upload.

Disk 0 seems to be a Legacy-MBR type and disk disk 2 is UEFI-GPT. For what I know, you won't be able to direct boot Win 10 or Win 7 (on drive 0) from the UEFI boot loader.
Disk 0 has one master boot loader (probably on the last OS installed)
First thing to do is to detach disk 2 (MVMe ?)
Boot from a Win 10 installation disk and do a boot repair on disk 0.
Once you're able to boot into win 10 on disk 0, do a bcdboot X:\Windows (replace X with the drive letter under Win 10 on disk 0)

Finally, to choose from disk 0 or disk 2 you don't need to change BIOS boot priority. Launch Boot Menu (F11?) during POST.

To check the disk type (MBR or UEFI) on Disk manager - View (top menu) - Top - List Disk
Or
Open a CMD window as administrator and type:
diskpart
list disk (see last columns)
exit
exit

Megahertz07 said:

Disk 0 seems to be a Legacy-MBR type and disk disk 2 is UEFI-GPT. For what I know, you won't be able to direct boot Win 10 or Win 7 (on drive 0) from the UEFI boot loader.

It works on this topic:

Bootmanager, nachtraglich Windows 7 als DualBoot erstellen | ComputerBase Forum

From a UEFI boot loader, if you select a Windows on MBR disk it will reboot first and then load Windows, so it's not direct.
Makes more sense to launch the boot menu and directly choose the MBR disk. It will load a master boot load and then you can choose Win 10 or win 7.