ASPX page IIS 6.0 not displaying

Hi,

   I am having a windows 2003 server with SP2 installed. Recently installed IIS and ASP.Net installed through Add/remove programs.From IIS6.0 ,html pages are able to browse through rightclick. But ASPX files are not opening directly in IIS6.0 , Error is page cannot be displayed. I had allowed ASP in webservice extension. Please help to resolve.

Regards

Bala