This is all for the better but requires some changes to you current project.

When you use the Gantt_ASP you would have had something like this in your aspx page:

We need to change it since the AjaxControlToolkit does not need the special ToolkitScriptManager any longer and it does not exist in the namespace.

Also the names of the scripts we rely on to move around time items has change names.

Your code should look like below if you use plexityHide.GTP.dll’s from after this date 2016-06-11.

Summary:

• Replace ToolkitScriptManager with ScriptManager
• Drop the attributes of ScriptManager ; CombineScripts and ScriptMode
• Change Common.Common.js to Common.js
• Change Compat.DragDrop.DragDropScripts.js to Compat.DragDrop.js
• Increase your applications .net version to 4.5