the "directory is busy" message just means that you have stray lock files in the machine.. download remlok32 from my web site, and let it find and delete all lock and net files on your drive..
I never heard of the file box.id, but a careful re-install can't hurt.. make sure you have backups, and that you don't let it change your defaults..
as always, the vast majority of all serious Paradox support can be found on
www.thedbcommunity.com