The solution is apperantly simple: you go in BIOS and reset to default all the settings....The problem is with the KEYBOARD...try to find another 2 keyboards..one with ps2 and one with usb...or as a last resort try replacing the ps2 port from the motherboard..

On the motherboard you will be having the 2032 CMOS battery cell remove that and replace that after 5 or 10 mins or put the battery cell new one and after that try booting your system then you will get the CMOS error after that try setting your CMOS if your keyboard works and save it and then exit the error will not come up again ..
if you are unable to identify the CMOS battery just refer to your motherboard manual it will be clearly mentioned where it is located ..

if you still couldnt able work with the keyboard then this may be due to 2 causes
1) The BIOS might have got corrupted ..
if so then change the BIOS jumper to recovery mode. to change to recovery mode just you can refer to the motherboard manual it will be mentioned more clearly how to do it ... once you do this the keyboard will work..

2) The capacitor near by the ports might have dead so due to that you might not get the power supply to the ports in the motherboard ..

if the capacitor is dead then you must visit the motherboard technician and get it replaced ..

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