It is also possible the print head itself has gone u/s. they do in hte main have a limited life and are often quoted by hte manufacturer as parts that need changing after so much use. however the...

water (& in my case wine) and keyboards do not mix. Laptop keyboards are two rubber membranes with a graphite type of mix a thte points where keys are. If these are damagd in any way it is a new...

u could try reinstall the mouse driver and check for viruses
Even a restore to a previous time might get it going.
M