OK so this is with my sisters laptop, everything was apparently fine one day & not working the next.
I've read it may be a driver issue & have re-installed the correct (I think) driver version, but this hasn't fixed the problem.
Is there anything else I can try..?
Hi, have you considered 'System Restore' ? This will allow you to return the machine to a point before the corruption. If that doesn't work try removing whatever caused the issue in the first place whether it be hardware or a software update.