CS1502 Error when Rendering a MVC Partial View

I am just getting up to speed on MVC3 with Razor and when creating a partial view ("_TestPartial.cshtml") and including it on another page through with:

    @Html.RenderPartial("_TestPartial") 

I got the error:

    CS1502: The best overloaded method match for 'System.Web.WebPages.WebPageExecutingBase.Write(System.Web.WebPages.HelperResult)' has some invalid arguments

Looking at RenderPartial it returns a void. Internally it writes directly to the response. A quick razor syntax change to:

    @{ Html.RenderPartial("_TestPartial"); } 


sorted the problem. Now for the interesting problem of getting MVC partials to render on classic aspx webpages.