Some files isn't work... How I can open it?
Your files isn't work because you don't have Codecs.

1- What is Codec?
Codec is abbreviation for (Compression/Decompression). It also stands for (Coder/Decode) and (Compressor/Decompresser) All
these variations mean the same thing. Coder (Compression) converts analog signals of audio/video files to digital files. Decoder
(Decompression) converts digital signals back to audio/video files. Therefore, Codec is device which both compresses and
decompresses various documents and audio/video files to compress the size of the files for less expensive transmission.
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2- Why do we need Codecs?
Video/Audio files are too large, The uncompressed file would be far too large to transfer across the Internet quickly, but the
compressed file could usually be downloaded in a few minutes. For example, 20-MB video might be reduced to 200-KB.
“Codecs”  were built to encode (compress) your video files for transmission and then decode it for viewing. Without Codecs,
downloads would that four to five times longer than that is was.

So thats why you need Codecs to Decompressed your Compressed Video/Audio files.
3- What Codecs were installed on my Windows?

  • Open Control Panel: Start>Settings>Control Panel.
  • select Sounds and Audio Devices icon, then select the Hardware tab.
4- What are the codecs I should use?
There are so many codec choices and the easiest option is to downlaod collections of codecs gathered.

You can use the following search box to search for free codecs.
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