Windows 10: Dual boot installation with Win 7 + 10 -- multiple issues

I wanted to experiment with Win 10 while preserving my Win 7 x64 installation. I imaged my Win 7 to a new hdd which is formatted as GPT. I repaired the Win 7 copy using a Win 7 SP1 installation dvd and got it to boot in UEFI mode using the "Windows Boot Mgr" option in the BIOS boot menu. So far so good.

My original plan was to keep my Win7 install on the original MBR disk and upgrade the copy on the GPT disk to Win 10. Within the running copy of 7 I ran setup.exe on the Win 10 x64 Build 0162 dvd. It started checking the PC, but after a minute failed with the error msg "Setup has failed to validate the product key." This happened before any prompt to enter the Win 10 ISO key. My Win 7 key is valid "Genuine Microsoft", so I don't know what's going on with that.

Search for that error suggests corrupted Win 10 install media, so I tried clean-installing Win 10 to a separate partition on the new drive. It installed successfully. On reboot, I am presented with a new Win 10 boot menu that offers the new Win 10 by default, as well as the Win 7 copy on the GPT drive. During the Win 10 install, the new drive was the only one in the system. After installation, I reconnected one of the other drives. Win 10 will still boot, but the Win 7 option on the boot menu fails with error 0xC0000225. Since it would boot when only one drive is installed, I'm wondering if there's a drive numbering problem involved.

Is there any way under Windows 10 to view and edit the entries in the UEFI Boot Manager? On MBR disks I used EasyBCD to maintain the boot entries. I remember on XP having to change the drive numbers in boot.ini when drives were moved or added. How do you do that for UEFI boot? (EasyBCD does not support UEFI.)

The last issue had to do with ChkDsk running after I booted off the MBR drive to my original Win 7. I suspect that is caused by the "Fast boot" option in Win 10 being on by default. I've seen that problem before in dual-boot scenarios when hiberfile.sys is used by an OS on shutdown. I saw how to turn off Fast Boot, but I haven't tried it yet.

I appreciate any advice on the upgrade issue and the drive# issue in the Boot Mgr -- thanks.

:)

 

No dual-boot at all?!

You are violating the windows license agreement and will not be able to activate windows 10 if you did not upgrade from windows 7 on your boot drive before doing a clean install. The free Windows 10 upgrade replaces your windows 7 license and windows 7 cannot
be used or transferred after the upgrade. You will have to buy the license to activate windows 10 if you have not purchased it already.

If you are willing to purchase the win 10 license to activate it, here are dual boot instructions but windows 10 can be difficult to dual boot-- (win 7 instructions are the same for win 10)

http://windows.microsoft.com/en-us/windows/install-multiple-operating-system-multiboot#1TC=windows-7

Custom installation of the newest version with drive options is the key to dual booting. Changing boot order in the bios doesn't apply to dual boot. You will have to do a Custom Clean reinstall windows 10. Consider just staying with windows 7 until you replace
the computer.

 

Dual boot installation?

I currently dual boot Win 7 and Win 8 on my Dell PC. I want to do the clean install of Win 10 on the Win 8 partition. My question is will it affect the Win 7 partition and will I be able to dual boot win 7 and Win 10?

Thanks,

Brian

 

Found this on the TechNet Win 10 forum, just posted a few minutes ago:

That's the most likely explanation of the key validation issue. That leaves the boot menu issue to resolve.

 

All pre-release Win 10 Insider Preview prod keys have been deactivated - Windows 10 Forums