UpdatePanel - "Unknown Error"

I am using a drop down to fire the trigger on an update panel

This is my code:

<Triggers>
<atlas:ControlEventTrigger ControlID="DDLCountryID" EventName="TextChanged" />
</Triggers>

When I click on the drop down, I get "Unknown Error".

Your help is appreciated.

Hi,

which release of ASP.NET AJAX are you using?

In the RC, you should choose between a PostBackTrigger or an AsyncPostBackTrigger.

updatepanel and "unknown error" popup already fix in AJAX?

Last time, I'm using atlas and when i'm using updatepanel, there is an "unknown error" popup after the session is expired. From what i know, that "unknown error" popup is a bug. Just want to know, is it the problem fixed already in AJAX?

i encountered same error with you, as last time using ATLAS.

now i changed to AJAX official release, the problem seem like gone.

everything works fine here.

thanx for the update