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Saturday, December 13, 2008

AJAX Error: 'Sys' is undefined

The error means that you're not getting the client side files loaded on your browser

So I ran fiddler to see what is happening and which file is not getting download.

After struggling to solve the error , this is what saved the day for me.

Web.Config: Make sure your web.config is correctly configured to handle AJAX enabled request. You might have created a project which was not AJAX enabled earlier and now you want to Ajaxfy. The best solution is creating a new project ASP.NET AJAX Enabled Web Site. It will create a Web.config file by default.

Or You can change Web.Config to add following

<add verb="GET"