I started my investigation by creating a simple Web Application targeting Framework 4.6. Decided to skip testing Framework 4.0 since the problem only happen when targetFramework is set to 4.6.

A web form, WebForm1.aspx, is added into the application. It has a WebGrid and an ASP.NET Button. The grid is bind to SQLDataSource control and shows Customers data. Initially, the grid is grouped by "Country" column with ascending sort order.

<ISWebGrid:WebGrid ID="WebGrid1" runat="server" Height="500px" Width="100%" DataSourceID="SqlDataSource1">
    <LayoutSettings AllowGrouping="Yes">            
    </LayoutSettings>
    <RootTable DataKeyField="CustomerID">
        <GroupedColumns>
            <ISWebGrid:WebGridGroup ColumnMember="Country" SortOrder="Ascending" GroupMode="Expanded" />
        </GroupedColumns>
        <Columns>
            ...
        </Columns>
    </RootTable>
</ISWebGrid:WebGrid>

Following code is added into the button click event handler.

Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
	If (WebGrid1.SelectedRowKeyValue <> "" Or IsNothing(WebGrid1.SelectedRowKeyValue)) Then
		Dim keyValue As String = WebGrid1.SelectedRowKeyValue
		Dim x = keyValue
		Dim name = WebGrid1.RootTable.GetUngrouppedRows().GetRowByKeyValue(keyValue).Cells.GetNamedItem("CompanyName").Text

		Button1.Text = name
	End If
End Sub

Following steps are performed in order to test the reported problem:

1. View WebForm1.aspx page in browser.
2. Select any row.
3. Click the Button1 (under WebGrid control).

Everything work as expected and I was unable to replicate the problem.

I enclose my simple sample as attachment. Please have my sample evaluated on your end and feel free to let me know if you find anything that I might miss during my attempt in order to reproduce the problem.

Glad to hear the good news.

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