Created Unassigned: Could not load control AjaxControlToolkit.TabContainer [27518]

Please see exception as follows:

例外狀況資訊:
例外狀況型別: System.Exception
例外狀況訊息: Could not load control AjaxControlToolkit.TabContainer. The script reference(s) of this control was not loaded correctly. If AjaxControlToolkit.config is used, probably this control is not registered properly.

執行緒資訊:
執行緒 ID: 5
正在模擬: False
堆疊追蹤: 於 AjaxControlToolkit.ToolkitScriptManager.OnPreRender(EventArgs e)
於 System.Web.UI.Control.PreRenderRecursiveInternal()
於 System.Web.UI.Control.PreRenderRecursiveInternal()
於 System.Web.UI.Control.PreRenderRecursiveInternal()
於 System.Web.UI.Control.PreRenderRecursiveInternal()