Hi, and WELCOME TO TECHIMO...!
If the computer has a PS2 connector, I would try that. I would also check that the USB keyboard is functional by plugging it into another (working) computer and seeing wheter you can type with it.
It could be that the USB slots either aren't connected inside the case or have been disabled in the BIOS. Also, if you're using a wireless keyboard it normally wouldn't be usable until the OS has loaded.
Let us know how it goes.....
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