My internet service provider tells me that I have gone well over my normal monthly usage for download/upload - 5 times more infact! In the last month I have hardly used my internet. As my excess internet usage fee has sky rocketed, is there a way how I can see what or who has been uploading or downloading using my internet? My internet service provider tells me it was over a 3 day period at the start of last month. My temp internet folder is strangely empty. Yes, I have a wireless router but it is security password protected. How can I get to the bottom of this?

download and use netlimiter: http://www.netlimiter.com/download.php NetLimiter 2 Monitor it tells you exactly the bandwidth used by each internet application.

Thanks Darksonic, that is useful, but is there anything I can do after the event? I need to see who downloaded via my router