As Yi-Lun mentoined, your requirement is REST and not SOAP.
1-In VS, Create WebApplication of any kind.
2- Temporary set the project to .NET 3.5 (default ist .NET 4.0)
3-Click on AddNewItem and type AJAX in the search text box on top right.
4-Select AJAX Web Service (change default name Service1.svc to anything else)
5- VS will create all you need including configuration.
6- Set project back to .NET 4.0. This switchig was just to explicitelly say to VS to create configuration. If you do not wont to see it you do not need steps 2 and 6.
Damir Dobric
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