Okay I hate to add to this but I used to be an amiga dealer, so I am going to add to your questions..
as stated before device letters for hard drives on the PC like C:, D, E, don't exist. A and B are not floppy drive letters.
on the Amiga DF0:, DF1:, DF2: are drive letters just like a and b are
DH0:, DH1:, DH2:, HD0:, HD1: are normally assigned drive letters and names, they could also be SYS:, WORK: the names are completely assignable by the OS..
All of that is scriptable by a batch file (the namings). Some older Amigas weren't equipped with a hard drive and run their software off of multiple floppy disks (the Sys: using being the floppy disk it booted from the workbench disk).
In some very old software for keeping track of people, accounting, etc. if you didn't have a hard drive the software ran a batch file to boot up from that re-assigned drive letters because on the Amiga they are completely assignable. Since a floppy based system didn't have a DH0: or a DH1: or a HD0:, or HD1: people would alias those drive letters in the batch file to match the names of the floppy drives, so they could run one batch file and their drive asssignments for where to find files and system stuff that the would use would still work.
So the question you have to ask yourself is does your system really have a Hard Drive in it.. We need to know for sure. If so formatting the hard drive as you suggested you did probably damaged the system, and you will need to reinstall the system software onto it.. Don't sweat it, because that can probably pretty easily be done if you still have all the floppies that came with the system. You might have deleted data though (Which could be lost without disksalv or quarterback tools). Try quarterback tools first. Disksalv didn't support hard drive recovery until really later versions of it.
all of the batch files or scripts on the amiga are usually stored in an aliased or assigned directory called S:
device drivers are stored in an assigned directory called devs:, Commands in C:, handlers in L: on the sys: drive but even those things can be moved elsewhere..
I hope this further clarifies..
