The problem is that
var str = Course_ApproveCourse.Load_Data('abc');
Isn't defined as a method in JavaScript. I've not used AjaxPro, but it looks like it could be one of a few things, this looks your most likely solution:
http://stackoverflow.com/questions/2715515/asp-net-2-0-c-sharp-ajaxpro-registertypeforajax[
^] - you need to prefix the
Course_ApproveCourse
with the namespace of the
Course_ApproveCourse
asp page. The other thing is that (I assume) AJAXPro generates an on-the-fly JavaScript that contains this method - this could be missing?
One a separate note - I suggest you download a tool called "Fiddler" - it lets you see what is passed up and down the wire on each call. I am not affiliated with fiddler, telerik or any of it's partners, at least not as far as I'm aware :)