' This is a form with 2 buttons, one to create the form and one to close the other form.

Public Class Form2

    Public Class myForms
        Public Shared FirstForm As System.Windows.Forms.Form
        Public Shared SecondForm As System.Windows.Forms.Form
    End Class

    Public Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        myForms.FirstForm = Me
    End Sub


    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim myform4 As New Form4
        myform4.Show()
        myForms.SecondForm = myform4
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        myForms.SecondForm.Close()
    End Sub
End Class