Title: AjaxControlToolkit.dll 1.0.10123.0
Tags: c#;asp.net;ajax;ajaxcontroltoolkit
Question: which .Net Framework version is support this version of (AjaxControlToolkit.dll (1.0.10123.0)) and which is not?
i have confusion about this, i m using visual studio 2008 Pro .Net Framework 3.5 and when i add the AjaxControlToolkit.dll version (1.0.10123.0) to bin folder then the ajaxcontrolstoolkit is work fine in my project but when i replace it with  AjaxControlToolkit.dll version(3.5.60919.0) then it does not give any response and by default when i add any ajax control to my web form then it is automatically replace the version(1.0.10123.0) with the version(3.5.60919.0) but it does not work with the version(3.5.60919.0).


Here is another answer: Clean the project and try to install as below
you can follow this install steps. you need to download AjaxToolKit for .net 3.5 from Here. After you add the ajaxtools to Visual Studio Toolbox, drag and drop the AjaxToolkit Script Manager to Your page. Don't use default script manager control

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