If Your Atlas Update Panel Doesn't Work...

If you every find yourself trying to add MS Ajax (Atlas) to an existing application and find that no matter what you do pages keep posting back instead of making asynchronous calls, you may want to poke around your web.config file.

At PDSA, we have a code generator that will build a new application based off our framework. I was tasked with adding Atlas support to one of these applications only to find out that the UpdatePanel, try as I might, would not work in our project.

After some investigating we found that the web.config had a curious entry in it:

<xhtmlconformance mode="Legacy" />

Once we removed this line in the config file the Ajax requests worked as advertised!