If I mount a portable hard drive as a folder in Windows 10, can I still use that drive as a portable drive on another computer?

Solution 1:

Unplugging the drive requires for it to be dismounted first.

If you use it on another computer without dismounting first, you risk the meta-data on the disk getting out of sync with the version stored in the computer memory.

Mount the disk again after plugging it in.

Solution 2:

Yes. Mount settings are stored by the OS, not in the filesystem that's being mounted.