cant open jpg pics sent from my friends mac

My friend has sent me all my pics from a recent trip to Thailand but when i try and open the files on windows 7 it says the files are either corrupt or not supported, my friend has a mac and i am wondering if this is the problem, i have tried extracting the files etc with no success, any ideas?

Do the files have a file extension on them? if not, and if you are sure they are .jpgs....then add that to the filename. Example, change Picture001 to have a file name of Picture001.jpg.