All USBs have stopped working on my PowerEdge SC430

Check the BIOS Setup (F2) to see if somehow the USB ports are disabled there.

If it is enabled, you can try clearing the NVRAM using the jumpers on the motherboard.

If neither works, you are most likely looking at a motherboard replacement.

As a workaround, you should still be able to boot into the OS, then Remote Desktop into it (if enabled).

JSL,

Did anyone access the BIOS and disable the USB's? Also are all the USB, front and back, not functioning?

If so then the issue may be greater than the USB board, as the 2 on front are on the control panel, not like the remaining ports.

What exactly is the server doing when you power it up?

This is the situation I am in.  I took this basically as "consulting work" for a local business here.  I was given this computer and basically was told it was working all all of a sudden it stopped working.  All it has is 4 USB ports in the back and 2 in the front.  I can not connect a keyboard or a mouse to this computer because it does not have the "old fashioned keyboard and mouse ports on the back.  I ran a few tests....I powered on and basically at the start up screen I got a keyboard error code.  It proceeded to load its OS, Windows 2003 Server and thats basically as far as I could go because the computer does not have access to a mouse or a keyboard.  I tried buying an external USB (externally powered) but when I plugged in my mouse and keyboard to the external USB, the USB still did not work.  I even tried removing the motherboard battery (took it out for about 10 minutes) and put it back in but the onboard USBs were still dead.

I can not use the keyboard or mouse on it so I can not get into the BIOS setup.