Urgent! - How can I disable a LinkButton on a Web Form?

Hi,

 I am fairly new to .Net so I need to learn how to disable a Link Button that is on my web form.  Here is what I am trying to accomplish:

 1.  A user clicks on a button to ADD a new record
 2.  I would like to disable a certain LinkButton whenever the user has entered the Add Mode

How do you do that?

Thanks!

J.Vega
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