Dreamweaver: Step by step instructions on changing default extension?

I asked this in another category section with no results, so I am asking in this section.

Can anyone give me step by step information on how to change the default extension from .htm to .html (when I save a new document for the first time)? I know you are supposed to do it from the "preferences" menu, but I can't seem to figure it out.

The box that shows the default extension is .htm and it is "grayed" out so I can't edit it from there. I can choose the HTML from the drop down list above it, but it keeps the default to .htm. Does that make sense?

Thanks for your help.

Dreamweaver: Step by step instructions on changing default extension?extension

You'll need to edit the "extensions.txt" file, and also a file called "MMDocumentTypes.xml"

Here's a step-by-step on how to do it, direct from "the horse's mouth" (Adobe)...

Dreamweaver: Step by step instructions on changing default extension?movie theater opera theater

I'd really like to help, but I'm pretty computer illiterate,

sure there's a geek or two that will give you a hand if

you let your question ride for awhile. -- Sorry :0[
I'm using dreamweaver in my html class (i'm in school for web design) and when we started saving pages or files in dreamweaver, we just changed(typed) the extension to .html ourselves, and then it defaulted to ".html" every time after that. But I'm a pretty new user to Dreamweaver so there may be another way to set it that is more technical :-D