After installing IE7, all HTML files display the IE7 icon, whatever program (browser or HTML editor) is set to open these files.
I’ve tried the advice here with no luck:
control panel → folder options → file types
http://forums.mozillazine.org/viewtopic.php?t=473158&sid=2aa5fb51a5c60cc3aeb9cbf6545e033f
If anybody comes across a solution. please let me know!