Is it possible to identify files in use?

[ka jowct]

I am using a font manager, but I shut it down, which should deactivate all but the system fonts. I also checked the open fonts' file paths (which was very tedious). They are all where they should be.

This problem is specific to this one drive (my main boot drive). I can boot from a different drive and run DW just fine. However, I would like to know what the heck this drive (my main boot volume) thinks is open on the drive in question.