In the KeyPress Event of TextBox1 , put this code . Number 13 is the ascii code for Enter Key , in case you don't know it already .

VB Code:
  1. Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
  2.         If Asc(e.KeyChar()) = 13 Then
  3.             TextBox2.Focus()
  4.         End If
  5.     End Sub