Did you install the samsung drivers? On that link I posted, there is a link for the samsung drivers to install on your computer. As long as you read the instructions step by step, you should have no problem whatso ever. After you install the drivers, reboot your cpu, then plug your usb cord into the computer (not in your phone yet), open up odin, make sure your phone is off, plug the other end of the usb cord that's already plugged into your computer to your phone (while it is off, hold down both the + and - volume keys but do not touch the power button), then you should see a yield sign on your phone screen that says download mode, after you see that screen on your phone let go of the volume buttons, then you should see a yellow box on odin with one of the ports it's using, then just follow the steps.