Right-click the Toolbox and select (name it "AJAX Toolkit"). Right-click inside the new tab and select Choose Items .
: Remember that most toolkit controls require a ScriptManager or ToolkitScriptManager on the page to function correctly. Download Ajax Control Toolkit zip
Browse to the AjaxControlToolkit.dll to populate the list with controls like CalendarExtender , Accordion , and ModalPopupExtender . ⚠️ Security & Versioning Note Right-click the Toolbox and select (name it "AJAX Toolkit")
: If you download the DLLs manually, right-click References in your project, select Add Reference , and browse to the extracted AjaxControlToolkit.dll . right-click References in your project
: To see the controls in your Visual Studio Toolbox: