My viking mp3 3.52 player is closed decode not playing

A lot of media players can play MKV files on your computer. If you're looking for a free program, just give Leawo Media Player a try. Besides playing MKV and other media file formats, the tool is also a good Blu-ray/DVD player for your computer.

6 Best Free MKV Players for Windows to Play MKV Files on PC for Free

Many video files require a custom codec (a decoder/encoder). There are codec packs you an download and install that will play most if not all video files. Google "windows 7 codec pack". Don't forget to run your anti virus check on it before installing.

It could be the permissions for SD card.
Please post logcat log.

A lot of free dvd decoders are available at this link:

http://www.freedownloadscenter.com/Search/dvd_decoder.html

If you are looking to play DVD files i.e. VOB files then you can play it using VLC player.

Follow the below link to download VLC player.

www.videolan.org

VLC player plays almost every file format and it does not needs any extra codec to run the files.

Here you can download flac decoder

http://flac.sourceforge.net/

Chances are you need the proper codec to run the DVD. Software companies often write their own 'interpreter' software to read the format they use to encode videos/music files.

Trying doing a search on the internet for the type of file format Windows Media Player is trying to run, then look for the codec for that format. Unless the format is copyright protected, Microsoft should have the codec available on their website.

To play RM file you need to download and install Real Player. Click RealPlayer.com to download.

You need a piece of software to play DVD movies. Is this an actual DVD movie, or is it an MP4 or WMV/WMA file?

Usually you need something like WinDVD to play a DVD movie. I don't think Media Player can play those.

Did you recently install another piece of software that might have affected your ability to play DVDs?