Probably you are missing the reference... Thanks Md. Marufuzzaman Don't forget to click [Vote] / [Good Answer] on the post(s) that helped you. I will not say I have failed 1000 times; I will say that I have discovered 1000 ways that can cause failure – Thomas Edison.

You need to install ASP.NET AJAX server extensions. This will add necessary assemblies to GAC. Navaneeth How to use google | Ask smart questions