Mouse troubleshooting

[bamanadasa]

i hav a optical ps2 mouse.recently left click stopped working.and it started to go nuts.cant select windows etc. i tried a usb mouse but da the problem is still there. it is not a virus because i fully formatted the hard drive and the problem is still there.pls help

 

[darklord4]

Try plugging in to other usb ports. is it only the left button that doesnt work?