I want to search a single drive specified by the user or all drives if the user de-selects the check box to limit to a single drive.

However, I want the all drive search to limit to Hard Disks only (ignoring Floppies and CD's, zip drives etc). I have visualised a function which returns a string containing only the letters of the hard disks on the PC. I can then use this string to perform a search and update a database of specific files when it finds them.

I am pretty sure that there is an API call to do this but I can't find any information about it and it's got me pulling my hair out.