If I wanted to install a different operating system for experimentation, would that overwrite the Windows 10 OS already in use, meaning I couldn't go back to it, or would W10 remain on the HDD in another partition and can be safely retrieved? Thanks .
You can install another OS on dual boot, on another partition or disk. Dual boot keeps your original OS intact. See tutorial: Dual Boot Windows 10 with Windows 7 or Windows 8 | Windows 10 Tutorials
I've made a short video showing how to install a second copy of Windows 10 for dual boot:
Video from Ten Forums video thread.
Kari
It's a lot simpler and quicker to run other systems as virtual PC using free virtual box as you don't have to mess with partitions or mess with the boot up
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