.NET 2.0 Web Service - removing Function in code does not remove it from WSDL

Using VS 2010, Win 7 x64.  
Created VB.NET 2.0 Web service.   I added a new Function to the web service.  The new Function works fine.
I removed the 'Hello World' Function in the code, and did a Rebuild.  When I press F5 to run the program, the 'Hello World' function still appears on the Service.asmx web page.
How can I remove the 'Hello World' function?
Thanks
 
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