If you preview a document that contains active content in Internet Explorer after installing the Windows XP Service Pack 2 update, the browser does not show active content. You can fix this problem by inserting Mark of the Web code in your document.
Internet Explorer blocks active content and scripting that tries to run in the Local Machine zone. For security reasons, Microsoft increased the restrictions on what can run in this zone by default. Mark of the Web code tells the browser to run active content in another zone, in this case, the Internet zone. For more information, see TechNote 19578 on the Adobe website at www.adobe.com/go/19578.
Dreamweaver inserts the following line in your code:
<!-- saved from url=(0014)about:internet -->
The line tells the browser to bypass the Local Machine zone and run the active content in the Internet zone.