How to tell what version of Windows is installed on a hard drive if windows can not boot?

Check this file   system root /Windows/System32 folder for a file called “ntoskrnl.exe”

Right click to check the properties

You will find the product version

4.x: NT 4.x
5.0: Windows 2000
5.1: Windows XP
5.2: Windows 2003 Server or Windows XP-64-bit
6.0: Windows Vista
6.1: Windows 7
6.2; Windows 8
6.3: Windows 8.1

10:   Windows 10