Dreamweaver and IE7 Problem

Having a problem with our Dreamweaver CS3 setup at present. When the students create a site and add menus or buttons to their pages on pressing F12 to preview the page in IE7 none of the buttons or menus are displayed just text and graphics. Unusually though any animations do display correctly. Have checked are filtering and have unblocked the use of .swf files and ensured that we have the latest shockwave player installed on the machines.

Slightly puzzled at present as to what might be stopping the pages from displaying correctly so any suggestions would be grateful.

Does they work in Firefox ?

flash installed and up to date and nothing blocking it such as anti virus or gpo?

Problem exists in Firefox as well.

After further digging discovered that Dreamweaver adds additional code converting tags to script for objects such as flash items like buttons. This basciaclly screws up the displayed page.

By editing the code removing this additional code the page displays fine. My problem is that it would be unrealistic to expect students to edit the code for every button or naviagtion bar within there pages, especially the year 8's.

Does anyone know of a way to tell Dreamweaver to stop this process.