Hi JMM,
Are you 100% sure your granddaughter sent the video and that it's not a fake that contains a virus?
Is Hotmail giving you an error message when you try to download the video file?
Hotmail does automatically block lots of attachment file extensions.
If you are sure it's safe to download, and Hotmail refuses, try
installing the Window Live Mail email program on your computer and use that to download and open the email from your granddaughter.
Please let us know if you need more detailed information for this solution.
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