Windows 10: Win10+Win7 dual boot issue

Dear all,

I hope I have not missed a thread with a similar problem:
I had Win10 installed on drive C: with the boot loader on drive D: (where I previously had my old Win10 installation). I wanted to add Win7 to my PC and formated drive D: - I totally forgot that I had the boot loader on that disk... Now I have Win7 on drive D: and drive C: is unchanged but I can not boot into Win10. I tried all the bootrec /fixmbr stuff, but found that my drive C: is not a MBR but a GPT...
Is there a way to access my Win10 installation without reinstalling the whole thing?

Thanks in advance!

:)

 

win10 home auto powers on by it's self

So this did fix the booting into win10 first issue, i can now boot into win10 or win7 from the BCD boot menu and the win10 boot menu doesn't interfere or cause a dual boot to get back into win7.

 

ual boot system upgrade to windows 10

Thanks Jessen for the hint. I was expecting a yes or no answer, since I already have a dual boot system(xp+win7), and if I upgrade win10 from win7 boot, would win7 be replaced by win10 and becomes a (xp+win10) dual boot system?

But it looks more complicated than I thought, should I check current system has xp and win7 are installed in DIFFERENT partitions, otherwise xp would be gone after win7 is upgraded to win10 if xp and win7 are in SAME partition?

 

What drive letter is your Windows 10 partition getting in Windows 7? Let's say it is D:\. Open an elevated ("run as administrator") command prompt in Windows 7. In the elevated command prompt Window run:

BCDBOOT D:\Windows /d /addlast

The path in red will be to the Windows folder on the Windows 10 drive letter.

Then reboot the computer.

 

The BCDBOOT D:\Windows /d /addlast command did not work in win7, but BCDBOOT D:\Windows did the trick - now the boot manager of Win10 is active and i can choose both OS! Thanks a lot!