Master Pages : how to remove headers/footers etc.

[Jethro]

HI all

I've inherited an ASP.NET 2.0 project, which uses master pages.
Basically we have :

MASTER PAGE
<asp:contentplaceholder id=cp1/>
<asp:contentplaceholder id=cp2/>
<asp:contentplaceholder id=cp3/>
<asp:contentplaceholder id=cp4/>

ASP FILE
<asp:content id=cp1/>
<asp:content id=cp2/>
<asp:content id=cp3/>
<asp:content id=cp4/>

Now if I want to just serve up what's in contentplaceholder2, do I
have to make changes to the ASP pages using the masterpage. I ask,
because I tried deleting them from the master page, and got runtime
errors about not finding the missing placeholders.

Or is there another way ?

The reason is that I have a partner who needs just the content of the
webapp Iin an IFRAME on their site), not the header, footer and menu
elements

thanks guys