Declare a string in the Application setting .
cntTab string
call this code in the TabControl_SelectedIndex Event: Dim idx As String
idx = My.Settings.cntTab
MessageBox.Show("Pervoius Tab Index" & idx.ToString())
My.Settings.cntTab = TabControl1.SelectedTab.Name
My.Settings.Save()
Call this Code in the Form Load Event: My.Settings.cntTab = TabControl1.SelectedTab.Name
My.Settings.Save()