It seems that the page is posting back and this is causing the RadLightBox
to close. Could you please ensure that this is not the case? Bare in mind that if the page postbacks it is expected for the light box to close as the entire page is being refreshed. In order to provide a precise answer on why are you experiencing such behavior I would like to ask you to share with us the contents of the problematic page.
As for isolating the light box from the rest of the page you can try ajaxifying it. That way you will be able to update certain parts of the page without entirely refreshing it.
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