How to: Update a Project Web Reference
If your application contains a Web reference to an XML Web service that has been recently modified on the server, you might need to update the reference in your project. For example, you might need to update a Web reference when new methods are added to an existing XML Web service. In that case, you need to generate a new proxy for the Web service so you can access the new method; this happens automatically when you update the Web reference.
To update a project Web reference
In Solution Explorer, open your project's App_WebReferences folder and click the node for the Web reference you want to update.
Right-click the reference and click Update Web Reference.
The new files for the XML Web service are downloaded to your project. Information for the XML Web service is updated within your project.