Dual boot Windows 8.1 & Windows 10 9879 / Winload.exe error

I'm running 8.1 and Windows 10 beta in a dual boot. Each time W10 updates it breaks the dual boot and throws the digital signature / Winload.exe error. From reading other posts I understand that W10 brings with it a newer winload.exe while 8's is older and that seems to be the problem.

How does one resolve this issue? Can the newer winload.exe be copied to the system32 folder in Windows 8.1?

Thanks for any insights.


---------- Post added at 09:19 AM ---------- Previous post was at 08:11 AM ----------

I wanted to report that I found a thread which indicated the process could be remedied by copying the newer boot manager (on Windows 10 TP) to the older systems (Windows 8.1).

The attrib commands did not work stating access denied. However, the DOS copy commands worked perfectly.

I can now dual boot 8.1 with 10.
No I don't think that's true. At least that has not been my experience. I have dual booted 8 since it was in beta, first with Windows 7 and now with Windows 10.


Mostly Harmless
Staff member
Hey Vince!

How's Windows 10 treating you?
Windows 10 is great,use it now more than Mac.
Windows 10 use efi boot, with wx, a memory load for security.
I had to reinstall after a MS update 10051. Stick with 10041 for now.
I would like to dual boot Yosemite, which I could with Windows 8