is it possible that when you select the TAB1 you can't select the remaining tab????

thank you much!!!<3

See if this helps.

Public Class Form1
    Private isTab1Selected As Boolean = False

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        TabControl1.SelectedIndex = 1 '// select Tab2.
    End Sub

    Private Sub TabControl1_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles TabControl1.SelectedIndexChanged
        With TabControl1
            If .SelectedIndex = 0 Then isTab1Selected = True '// if 1st Tab selected, set the Boolean to True.
            If isTab1Selected Then .SelectedIndex = 0 '// if Boolean=True, keep the First Tab selected.
        End With
    End Sub
End Class