1.
You should be able to play back the movie in the camera and watch it on the camera display screen.
Try that and see if you can view the movie.
2.
That camera will let you connect it directly to a Television set and let you view the photos and play any movies on the TV.
Try that and see if you can view the movie.
3.
If the above two test work OK, and the movie will not play on the computer, you need to use a different computer program to view the movie.
4.
If tests 1. and 2. do not work, it is possible that you are not executing the movie correctly:
I believe you just set the switch on the back to movie mode and then click the shutter button to start the movie and it will record until you press the shutter button again.
Check the Users's manual to review the instructions for doing a movie.
If you are using the 16 meg memory card that came with the camera, it is possible that you have run out of space on the memory card. A card with 16 meg of memory will only hold a few seconds of movie.
If it still will not perform tests 1. and 2. it is likely that the camera is defective. Take it back to WalMart.
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I recently bought the SD400 at Wal-Mart for $388. I love the camera but when I upload a movie to my PC the movie plays all black. I have tried everything but nothing has worked. If anyone could help I would be very happy!

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