Server Controls not working

I think this may have something to do with the mime type being returned. However, I am trying to transform XML into an .NET WebForm using an XSLT stylesheet with server side controls. I am transforming the XML into a string variable and performing a replace on that string variable to eliminate the 'xmlns:asp="remove"' text to create the final text that will be diplayed to the user.

Next, in order to get the HTML in the correct place on the page (mainly, after the HTML, HEAD and BODY tags) I set the text property of a server side label control to the string that contains the HTML rather than just doing a Response.Write(). I've used this technique in the past and have had no problems with it. However, the <asp:linkbutton> tags do not appear as links. Only the link text appears.

Finally, I viewed source and cut and paste the text into a test.aspx page (as-is) and everything displays correctly so I know the code being generated is correct. Any suggestions???