What does this mean exactly?
Couldn't Mount File
Virtual hard disk files can't be mounted from image files, or from removable media that isn't
formatted with NTFS file system.
I like 10 but being forced back to 8.1 because Speech Recognition not working so well for me like it did in 8.1
Anyway, I couldn't get my pc to install on bootup so tried installing with Windows running. Do I need to mount it through the ISO image on my harddrive?
Please try and describe what file you are trying to mount and what you hope to achieve.
If you are trying to restore back to 8.1 from 10 you have to restore from a backup you have made or recover Previous Version of Windows - Go Back in Windows 10 - Windows 10 Forums - you don't want to mount an ISO or VHD.
What's the status of your machine now? Win8.1 back up and running?
Post a screen shot of Disk Management and members can determine if three's enough space to install Win10.
If you dual boot, you get the best of both worlds. I recommend burning the Win10 ISO to a DVD disc and installing it from that.
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