I had this some years ago, the keyboard cable became entrapped between
the corners of two adjacent desks while the computer was on, resulting
in a dead keyboard and blown fuse on the motherboard. Replaced the fuse
with a small pica fuse and everything worked once more.

Okay. I can understand that on one keyboard, but not on three different
ones.

Sounds like a failure on the mainboard of the keyboard interface. Don't
despair. Buy a USB keyboard and mouse adapter (about $10) and see if that
works. Or you could replace the mainboard and rebuild the hardware... is it
still under warranty?

Well, that is just it.

I have four total keyboards - including the one that isnt working.

Two are without usb but have the dongle and two are usb.
NONE of the will work on this system now.
Not the USB dongle one OR the std usb one.

No, the computer is not under warrenty.. its a shuttle I built some time
back.

Ok, it is possible that the ps2 interface is blown and that usb keyboard
support is turned off in the bios. Or as someone else suggested a blown fuse
on the MB.
If it is the lack of usb keyboard support in the bios then resetting the bios
should enable it. Hopefully there is a jumper on the MB that will allow you
to do that.

The ps2 might be in fact blown. When you plug in the board all the
lights come on and then go off.

And USB support is on.

I tried another usb keyboard and it does work so, the dongle might be
bad.. or something else but right now Im just getting another keyboard
for the system.