ho creato questo, ma non funziona:

codice:
Dim sd As String, sa As String
        Dim i As Integer, j As Integer

        sd = "6369616F"

        Dim b() As Byte = New Byte(sd.Length / 2) {}
        For i = 0 To i < sd.Length Step i + 2

            For j = 0 To sd.Length Step j + 1

                b(j) = CType(UShort.Parse(sd.Substring(i, 2), System.Globalization.NumberStyles.HexNumber), Byte)
            Next
        Next

        sa = System.Text.Encoding.UTF8.GetString(b, 0, b.Length)

        RichTextBox2.Text = sa
come mai?