DO hangs up on a .wav file

DO hangs up when I try to select "Show or hide the Lister Viewer Pane" on a WAV file (~76 MB).

Also the Task Manager is unusable (more or less) after I've tried to destroy the DO process.

I've to close all programs and re-boot.

Any idea?

Disable the ActiveX and/or MultiView plugins to see which one is viewing the file.

If it's the ActiveX plugin then you can remove WAV from its config. It'll probably be listed under Media Player or Generic ActiveX, I think.