: Ensure your project targets .NET Framework 4.0 or higher , as recent versions of the toolkit do not support older frameworks.
: If you download the DLLs manually, right-click References in your project, select Add Reference , and browse to the extracted AjaxControlToolkit.dll . Download Ajax Control Toolkit zip
: To see the controls in your Visual Studio Toolbox: : Ensure your project targets
Right-click the Toolbox and select (name it "AJAX Toolkit"). Right-click inside the new tab and select Choose Items . Right-click inside the new tab and select Choose Items
: This is the modern standard for adding the toolkit to Visual Studio projects. You can install it via the Package Manager Console: Install-Package AjaxControlToolkit
: Right-click your project in Visual Studio, select Manage NuGet Packages , search for "AjaxControlToolkit," and click install.
The toolkit is no longer primarily distributed as a standalone .zip file from a central homepage. Instead, it is hosted and maintained through the following official channels: