Why i can not preview video files in thumbnail mode

Why i can not preview video files in thumbnail mode?

Do video files play okay in the viewer pane?

Is the Movie plugin set to generate thumbnails?

Is it all movie formats or only some?

No,all files cannot preview in the view pannel except imagin fiels.

Do the same videos play in Windows Media Player?

Is the Movie plugin enabled in Opus? (Preferences -> Plugins -> Viewers)

thx for reply.they can be played in WMP.the movie plugin have also enabled.
i can preview this video fiels in Window Explore and TC .

If you go to Preferences - Plugins - Viewers and click Configure on the Movie plugin, does it look like the screenshot below?

What actually happens when you try to view a movie in the viewer? Does the file get picked up by another viewer plugin and displayed in a different way? (At the top of the viewer pane it should tell you the name of the plugin that's displaying the file.)

Have you got any unusual video/audio codecs installed, or used any "codec packs"?

i have changed the Configure just like screen shot.
but the prioblem still exist.when i click the video file ,there is noting happened in the view panel.
i have try it in another PC,but i didn't find this problem.
i haven't install any "codec packs" yet.

Sometimes you can fix the problem by temporarily associating the file types you are trying to play to Windows Media Player. Could you give that a try and see if it makes them work in Opus again?

You should then be able to assign the types back to whatever player you prefer, but please test playback in Opus first in case assigning the types back to that player is what's causing the problem. (If it's what I think it is then it is just some registry settings that some programs fail to create when they overwrite the video file types.)