Creating a web service

1. I have installed Visual Studio .NET 2003 (few months ago) Now I need to develop web services so: 2. I installed IIS 5.1 from the Add/Remove programs of my Windows XP Professional SP2. 3. The I start again the Visual Studio .NET 2003 in order to add Web Service and ASP.NET developing support. But, when I want to create a web service project (with the IIS started and running) appears a message that says "Visual Studio .NET has detected that the specified Web Server is not running ASP.NET version 1.1. You will be unable to run ASP.NET Web Application or Services". Any clue? Thanks in advance.