Ajax client-side framework failed to load Asp.Net 4.0

Question

I got a complicated problem with ASP.Net 4.0 Ajax....I started a website with Visual Studio 2010 on my machine,and added some update panels they used to work fine,but sudden

Answer 1

I had this problem as well dealing with a master page and in my case it was a "Base" meta setting that was messing me up. I do recall reading another article/blog somewhere where they mentioned an issue with ajax validation across different domains causing this type of error.

So in my case, I had a reference setting the default url for the site but my dev was obviously a different url...thus conflict and the "ASP.NET Ajax client-side framework failed to load." error.

Removed the base and voila...error gone.

HTH

Dave