I have searched the forum and there are a number of questions asking if a preview is available before clicking play.

I ask for the specific case of wmv and mp4 files stored on my website server.  From the answers given I am still not sure what the situation is.  It is very unclear despite all the posts.

1.  Should Allvideos display a preview in this case or not?  I don't have a preview showing and am unsure if my setup is faulty or is "no preview" normal for this case?

2. If there is no preview in this case what is the action to take to get one?

Thanks
Derek Sharp