Check Device Manager and see if there is a flag denoting an issue. And a little more detail as to what kind of PC you have would help. As would more info on when this happened and what you did to make them stop working.
Check Device Manager and see if there is a flag denoting an issue. And a little more detail as to what kind of PC you have would help. As would more info on when this happened and what you did to make them stop working.