Thank you for the sent sample.

Unfortunately, it is not a working sample. Without the step by step information, I decided to directly check the code of WebGridResult.

Inside the OnInitializePostBack server side event of WebGridResult, I found the following line.

...
WebGridResults.ClientBindingSettings.DataSourceType = ISNet.WebUI.ClientDataSourceType.ServerDataSource;
...
WebGridResults.BindingOperationMode = ISNet.WebUI.BindingMode.ServerBinding;
WebGridResults.RebindDataSource();
WebGridResults.ClientAction.RefreshAll();

Could you confirm whether you are going to use client binding or server binding for WebGridResult?

I’d like to suggest isolating the specific problem in a simple sample. For example, there is a line of code which invoke the SendCustomRequest() method in OnPaneItemClick JavaScript function. After SendCustomRequest(), then WebGrid will call InitializePostBack server side event. We need to ensure whether the SendCustomRequest() is executed or not, since this method will call the OnInitializePostBack event.

I’m willing to advise you further but in order to do so I would need you to elaborate on your specific scenario and possibly give me a running simple sample and a step-by-step guide that I can use to observe the problematic behavior.