Need help to PROPERLY install dual boot: Windows 10 & Windows 10

In Macrium Reflect, drag and drop the old Windows partion only from the backup image file to the unallocated space on the target hard drive.

OK, the image doesn't show partitions. How do I display the image broken up into partitions? I clicked on "Browse Image" and a dialog box came up showing each partition. It's telling me to click a checkbox for the partition I want to explore and associate a drive letter in explorer. I'm doing this inside @Kyhi PE environment and I'm not familiar with how to get around in it. How do I find explorer and assign a drive letter?

I'm not at a computer now, but it is from the restore menu, you will select the image file you want to restore, not browse. Then select the target drive. Then in the upper half of the window you should see the partitions contained in the image file and in the lower half see the existing partitions on the target drive.

Then you will drag and drop the old Windows partition only from the upper half to the empty space on the drive in the lower half.

That's underway right now. Thanks - I should have known to do that intuitively. When the restore is complete, is there anything else I have to do to be able to dual boot?

Ok, the installation is complete - but the option to dual boot is not there. It only boots into the clean install.

Nisko said:

Ok, the installation is complete - but the option to dual boot is not there. It only boots into the clean install.

Your old Windows partition should have a drive letter. Let's say it is E:\. Change the drive letter below in the FIRST command to match what your old Windows partition drive letter actually is. In a Command Prompt (Admin) or "Run As Administrator" Command Prompt, enter the two commands below, change the drive letter in the FIRST command only to match what your old Windows partition got assigned:

bcdboot E:\Windows
bcdboot C:\Windows
exit

Reboot. Your new clean Windows install should be on top and default. The old Windows partition should be the bottom entry (after you reboot - I know the commands above are reversed!). Then open a Command Prompt (Admin) again and run:

bcdedit

Post the results here and I'll show you how to modify the description(s) to something meaningful.

@NavyLCDR Results of bcdedit BTW, I now have a working dual boot. Thank you again!!!

So, on your screenshot it looks like you are booted into the old Windows 10 and the new Windows 10 is the default? The way you change the description to something more meaningful would be to use the identifier field in the Windows Boot Loader Entries. So let's say the {default} entry is your new Windows 10 and {current} is your old Windows 10. You could do:

bcdedit /set {current} description "Windows 10 Old"

Then you can do just bcdedit by itself to see the change that was made.

bcdedit /set {current} description "Windows 10 Old"

Having trouble following the syntax. Especially {current} description. What do I substitute for that part of the command?