Tech question - file extensions...? (Mac users perhaps?)
 

I have a whole bunch of images which i think were created on a Mac. When i open the folders on a PC, the files don't have any extensions on the end and obviously don't open when double clicking. If i open IE and drag the file into there, the pics show but look pretty rough. If i add a ".jpg" extension the files do open and look perfect in Photoshop. (although rough in IE).
To get to the point, is there any program that can add the extension to these files in a few clicks??