My movie doesn't play

Useful FAQ in PowerPoint I found in the Internet:)
There are many reasons why your movie file may not play……
Source:http://office.microsoft.com/en-us/powerpoint/HA100777161033.aspx

Amazing PPT Hints, Tips and Tutorials
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http://www.tutorialized.com/view/tutorial/How-to-Convert-PowerPoint-Presentation-PPT-to-Video-AVI-MPEG-and-CD-DVD/34075

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What should be installed to convert all kinds of videos to FLV?

To convert WMV, you need to install DirectX 9 and WMV Runtime 9.
To convert MOV, MP4, 3GP, you need to install QuickTime.
To convert most of AVI, MPEG, you may download Combined Community Codec Pack (CCCP) from http://cccp-project.net and ffdshow encoder/decoder settings file from http://www.moyea.com/download/ffdshow_setup.zip, extract the ffdshow.reg from the zip file, and double click to import ffdshow settings.

Source--
Video&FLV Knowledge Originate from Moyea software

What is video Encoding?

Video Encoding is the process for changing a video from one format to another by altering the resolution and/or the bit rate. Normally the result of this process is a movie with a different compression. For a proper encoding you need a piece of software and/or hardware, which is called codec.

Source:Video Knowledge Base Originate from Moyea software