There are a couple ways to do this:
1) on edit button click you could store the current tab index; then on server side PageLoad you can check if you are using postback and if so, you can focus the tab you need.
2) you could use RadAjaxPanel and put the entire grid in there. That way only the page portion of the grid will be reloaded and not the entire page.
The second option should be much easier to achieve, as it requires just to wrap the grid. There is an example shown here -- http://demos.telerik.com/aspnet-ajax/grid/examples/dataediting/entityframeworkcrud/defaultcs.aspx
. Additionally, you may add a loading panel not to leave the users in the dark about the asynchronous stuff going on.
the Telerik team
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