emails containing video display the video as large blocks of text
characters.
How do I get Outlook to display video and play its accompanying audio?
I suspect you're seeing the raw MIME encoding. This is a sign you have
something interfering with Outlook's correct decoding of the data stream. The
usual offender is an antivirus program configured to integrate with Outlook
and scan incoming messages. If you have your AV program configured this way,
uninstall it completely, then reinstall it without the mail scanning feature.
It will not make you any more vulnerable to an attack it infection. After
doing this, have the sender of the original message send it again to see if
the behavior is different.
To handle the message you've already received, there are multiple MIME
decoding packages available that can process the message you've received if
you save it as a text file. One that I've used is by Mark Spankus and is
called UUD32Win.
http://www.marks-lab.com/