I am afraid that the provided information is not enough for us to pinpoint the cause of the problem. Can you elaborate a bit on the exact scenario in which the error is thrown? Can you to disable AJAX by setting the EnableAjax
property of RadAjaxManager
and see whether the problem persists? Is there any server-side error thrown after this?
If the error persists, please send us a runnable sample where the problem can be reproduced, so we can examine it further at our end.
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