AJAX control in ASP.NET

don't forget google is your best buddy ,there are tons of examples available that shows how to use ajax control toolkit. Need a place to start, here you go
http://www.asp.net/ajaxlibrary/act.ashx[^]
If you are planning to use ajax I recommend nice and easy Jquery ajax, google[^] and you will get your samples, good luck :)

No we can't. Not because we do want to, but the fact that you did not even specify which control you are trying to use? What is your problem? If you are getting any error, what kind of error message do you get? etc...

I would start looking at google[^], try a few examples, tutorials. trust me, internet is vast and there are so many people who have done this before. Go and take advantage of it....

You can start from here and here too.

But its recommended not to use ASP.NET AjaxControlToolKit if you can use jQuery Ajax.
Here you will find some links to begin with jQuery Ajax.