Windows crashes when I open a folder with a video file

[saeidmscs]

Hi every one
When I open a folder which contains some "video files" including types of 3GP,WMv,etc,windows crashes and this message appears:
windows explorer has stopped working
and then:
windows is restarting
then,like loging off,system starts again,but there is only one differnce and that is other programs which aren't related to windows explorer(for example,softwares like adobe acrobat,MATLAB,...)
,after that,continue to work properly!!!(I mean windows doesn't log off completely,sth like logging off occures)
What's wrong here?
What should I do?
Cheers

 

[septprince]

Are you using any codec packs? Which one??

Please check event viewer for error, if possible post a screenshot.

We could use some little bit more detailed information of your system.

 

[Pete1122]

The CoreAVC codec will cause this, are you using it?

 

[saeidmscs]

Sorry for being late!
Yes,I've installed 'Vista Codec Pack'(which homepage of it's publisher is http://shark007.net..