Force Download Link Files?

Hi all, I have some link to some files (.jpg, .doc, .xls) and normally when you "left" click on it, it would open the file. And if you want to download the file you would have to "right" click and "save as.." I want to enable my user to be able to download these files by just "left" clicking on the link. I have tried many things, I try linking it to a new php page and sent in some headers, my code: <? header("Content-type: application/octet-stream"); header("Content-Disposition: filename='ABC.gif'"); ?> However, it didn't work. Then someone told me to try this, <? header("Content-type: application/octet-stream"); header("Content-Disposition: filename='ABC.gif'"); print "bal bla bla"; ?> I did, this time it lets me save the ABC.gif (an dialogue box comes up and ask me to open or save), and after saving it, when I try to open my file, I see a big red X (the file is probably empty). I don't know why. Can anyone please help me? THanks a lot Kelvin