Errors modifying mounted image permissions + Error occurred while unmounting

I was going to transfer from Windows 7 to 8.1, so I used COMODO to backup my System drive and Data drive to a slightly larger hard drive.

Now I’m in my Windows 8.1 computer, trying to mount the System drive (as read/write) to get a few files from my old user profile. However, when I try to navigate into my user profile folder, windows says it can’t do that because I don’t own it. I open up the security dialog to go take ownership, but that doesn’t work either: “Unable to perform a security operation on an object that has no associated security.”

Ok, I think… Let’s try command prompt: “ERROR: File ownership cannot be applied on insecure file systems; there is no support for ACLs.” Huh? This is an NTFS file system, or rather, it should be.

I think go to unmount the image and mount it again, although COMODO continually errors out, saying that the volume is locked. There shouldn’t be any processes using it though, especially since the drive has disappeared from my Computer and Disk Manager. All that’s left is an unknown device in device manager. I remove the device, which causes COMODO to hang whenever I try to view the Mounted Drives tab, which also causes the System process to start reading and writing like there’s no tomorrow on the image in question.

Any ideas what’s going on here?