Hola, puedes hacer un pequeño metodo que reciba el valor y el objeto al que deseas despues del enter asignarle el foco..apoyandote del evento KeyPress
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y usarlo en los textbox que desees
Ejemplo..
Cita: Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
SetFocus(Asc(e.KeyChar), TextBox2)
End Sub
Private Sub TextBox2_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox2.KeyPress
SetFocus(Asc(e.KeyChar), TextBox3)
End Sub
Private Sub TextBox3_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox3.KeyPress
SetFocus(Asc(e.KeyChar), TextBox1)
End Sub
Private Sub SetFocus(ByVal iKey As Integer, ByVal objText As TextBox)
If iKey = 13 Then
objText.Focus()
End If
End Sub
Salu2 y espero te sirva..