please include your laptop specifications if possible...
if it would be an HP laptop then refer to this link ... otherwise please tell us more about the problem , like when did it start and what have you done so far...
http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01732674&tmp_task=solveCategory&cc=us&dlc=en&lc=en&product=5149092&query=QA598EA&tool=