how do I find out if the hard drive has windows 10 operating system on it?
Assuming you can get to the
\Windows\System32 folder in Windows Explorer, and see the file
ntoskrnl.exe, then you can right click the file and get the Properties up. In the Details you will see product version information:
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.x: Windows 10
This is on a Windows 7 boot drive:
This is on a Windows 10 boot drive:
and is it possible to boot from this hard drive?
What Dave said about the EULA and boot loops. If it boots at all, if the make and model are similar but not identical you might get erratic behaviour, if it is the exact same model, motherboard revision, CPU model and stepping, etc, it could be OK, BUT bear in mind the OEM hardware signature the install was activated against includes hardware serial numbers for CPU, hard drive, and motherboard chipset at least, so you are going to be way past the bar for a "significant hardware change" and you will most likely have to phone Microsoft and convince the agent you are entitled to a new activation code. Even if you don't face activation issues at the time of first trying it, a Windows update could put the system into the non-activated state, and if you have sold on the machine as having full legal Windows, you may get an angry customer banging on your door.