If you have an HP laptop sold from Sept 2010 through June 2012 (check anyway if later than this) then the power cord could be dangerous. Disconnect from the mains and check for LS-15 on the mains lead where it connects to the power brick. If is says LS-15 you are affected and should not use the power adapter.
Check here for information about a worldwide recall of affected power supplies http://support.hp.com/us-en/product/HP-Pavilion-dv6-Entertainment-Notebook-PC-series/4011364/model/4036197/document/c04404446/
CBits takes no responsibility for this information, errors, or omissions. This is for information only. You should check with the manufacturer directly.