AsyncPostBackTrigger not resolving in markup code.

[Guest]

To all,
I have a simple web site using a webform and I'm tryting to handle a button
event outside of my update panel. However, when I add the code below the
asyncpostbacktrigger will not resolve from intellisense. Therefore, the
build or recompile will not complete.

I have successfully installed all the necessary files for AJAX 1.0 but don't
know what is going on. Any ideas.

<triggers>
<asp:AsyncPostBackTrigger ControlID = "btn_Test1" eventname="click" />
</triggers>


Thanks,
Michael