color changes in photos after exporting from aperture and viewed on another computer

Help! I import raw images, I'm Proofing with sRGB IEC61966-2.1 and my colorsync profile in my export settings are also set with sRGB IEC61966-2.1. When i export to my computer the pictures look exactly as they should be, but when i email them and see them on other computers the colors are not at all what i be;ieved to have been exported! Im a newbie to the digital world...