Restore database error

Hi guys. I'm trying to restore the database using this code:

Code:

---

        Dim con As SqlConnection = New SqlConnection("Data Source=localhost; Integrated Security=SSPI; Initial Catalog=master")
        Dim cmd As SqlCommand

        If (MsgBox("Restore Data?", MsgBoxStyle.YesNo, "CSIS Data Backup")) = MsgBoxResult.Yes Then
            If (MsgBox("Restoring data requires that the application be closed after restore process. Continue?", MsgBoxStyle.YesNo, "CSIS Data Backup")) = MsgBoxResult.Yes Then

                con.Open()
                cmd = New SqlCommand("ALTER DATABASE CIS SET SINGLE_USER WITH ROLLBACK IMMEDIATE", con)
                cmd.Connection = con
                cmd.ExecuteNonQuery()

                cmd = New SqlCommand("RESTORE DATABASE CIS FROM DISK = 'C:\\CIS.bak';")
                cmd.Connection = con
                cmd.ExecuteNonQuery()

                cmd = New SqlCommand("ALTER DATABASE CIS SET MULTI_USER WITH ROLLBACK IMMEDIATE;", con)
                cmd.Connection = con
                cmd.ExecuteNonQuery()

                MsgBox("Data has been successfully restored. Application will now close.", MsgBoxStyle.Information, "Data Restore Successful")
                con.Close()

                End
            Else
                Exit Sub
            End If
        Else
            Exit Sub
        End If

---

But I keep getting this error:

Changes to the state or options of database 'CIS' cannot be made at this time. The database is in single-user mode, and a user is currently connected to it. ALTER DATABASE statement failed.

And it points to this code block, and fails to execute the query:

Code:

---

con.Open()
                cmd = New SqlCommand("ALTER DATABASE CIS SET SINGLE_USER WITH ROLLBACK IMMEDIATE", con)
                cmd.Connection = con
                cmd.ExecuteNonQuery()

---

Anyone know how to fix this?

You need to change your connection to another database on the server inorder to do a restore. No one can be connected to the database if it is being restored.