Double Click a button doesn't create event handler

Hello there,

I have Vista Home Premium installed on my computer and working with Visual Studio 2005.

We all know that double clicking a control creates the associated default event handler for that control in the code behind. 
But, in my case I have these button controls on my web form, and I am not able to generate event handler when double click them.

Can anyone suggest what is going wrong here?

Thanks in advance!
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