I cannot reproduce the issue at my end. Make sure that you are using advanced data binding using NeedDataSource event to bind the treelist. Also check the following help documentation. Simple vs Advanced Binding.
Problem the same I can expand/collapse before I click on btnSearch after it any node can not be expanded/collapsed and OnRespondEnd evend not fired on the client. Please help.
answered on 07 Mar 2012, 10:47 AM
The presented demo works correctly on my side. Test it locally and verify what the difference in your case is.
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