If it's a USB mouse and your PC has an old PS2 connection, try a USB-PS2 adapter.
If it's a PS2-mouse try a USB mouse
If it's a USB mouse, try it on another USB port
If it's a USB mouse, try another mouse (but you say you already did and it didn't work)
Do other USB devices work on that same port?
Finally, make a Linux disc or stick (that's free), boot from it and see if the mouse works there.
Hello,
I am Nduka Okoye. I am using Pentium Dual Core processor. It was all working fine but unfortunately my has stopped detecting the mouse device. I changed the device but its not detecting even I can't see the device in hardware portion. What is the problem??

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