I have an application that I wrote that uses a web service to provide data back to a central app. I needed a windows sidebar gadget to consume the web service. However I noticed that when using javascript to consume the service I would get errors. I then realized that I had to enable my web service to allow for access via HTTP GET. This allows the web service URL to be accessed using a string with any parameters added to the string. To enable this on your ASMX web service you just need a few parameters in the web.config.
< webServices>
< protocols>
< add name=“HttpGet“ />