It is not referenced in my "ASP.NET AJAX-Enabled Web Site" project.
It's not a video link, just description of the configuration elements.
You can have multiple web.config files for the application, they apply from child folder downwards if not overridden, and you only need the AJAX configs for those pages that use it.If I am not mistaken it looks like you can have a web.config file for each folder. Should I copy the AJAX settings into the web.config in my main root folder or only the web.config file in the folder where I am running AJAX related controls?
You can have multiple web.config files for the application, they apply from child folder downwards if not overridden, and you only need the AJAX configs for those pages that use it.