PHP 4.3 // DWMX04

Can anyone help me with this,

I have used php a few times in websites and it has always worked fine, in fact
last week it was running on my machine with no problems.

Today I started a new project and, I dont know how else to describe it other
than it just doesnt work anymore. Now when I preview my page from dreamweaver
I can still see the php in the code when I view the source so it hasnt been
parsed.

I am running apache and all previews are done locally, just as I always have.
Does anyone have any ideas???

Thanks in advance for any help