how do i download video using my sd card. it will not allow me to
Exactly what are you trying to do? Downloading usually means getting files from the internet - is that what you are referring to? Or are you trying to copy a video from your SD card to the computer?
If you insert your SD card, do you see it on your desktop? If so, you should be able to open that and simply drag your video to your desktop. Or directly import it into iMovie.
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