If the problems appeared after the installation of internet explorer7 follow this steps:

1. If the trailers pops-up a window where the movie will be played see if a check box appears on the screen asking you if to block the pop up or allow it.

2. Install media player 11 from here in case you dont have it.

3. Now try to play a trailer that worked before you had these problems.

Note: If you are open minded and like new things we recommend you Firefox 2 which has a new spell check program and runs faster and more efficient than Internet Explorer 7. You can download Firefox2 from here