Excel Mod and VB.NET Mod give two different answers

I've gave you an answer in the previous post[^].

Because you have an answer, i shoudn't help you... But i decide to show you how to achieve that using class.

Steps to do:
1) Create new project (Windows application)
2) Place on the form 3 controls:
- Label1
- TextBox1
- Button1 and rename it Name as CmdVerify
3) Insert into project 3 items:
- new class (change its name to: TBarCodeVer)
- new interface (change its name to: IBarCodeVer)
- new module (change its name to: ModMain)
4) copy the below parts of code and paste it into destination modules
IBarCodeVer.vb

Public Interface IBarCodeVer

    Property MemberShipNumber() As String
    Function BarCode() As String

End Interface

TBarCodeVer.vb

Public Class TBarCodeVer
    Implements IBarCodeVer

    Private sNumber As String = String.Empty
    Private Const sFirstSet As String = "279"

    Public Sub New()
        'do nothing ;)
    End Sub

    Public Property MemberShipNumber() As String Implements IBarCodeVer.MemberShipNumber
        Get
            Return sNumber
        End Get
        Set(ByVal value As String)
            sNumber = value
        End Set
    End Property

    Function BarCode() As String Implements IBarCodeVer.BarCode
        Dim sNumbers() As String = Nothing, sTmpNumber As String = String.Empty
        Dim i As Integer = 0, iCount As Integer, sRetVal As String = String.Empty
        Dim iSum As Integer = 0

        Try
            iCount = sNumber.Length
            If iCount <> 16 Then
                MsgBox("The length of MemberShipNumber must be equal 16!", MsgBoxStyle.Exclamation, "Error!")
                Exit Try
            End If

            sTmpNumber = sNumber
            Do Until i = iCount
                ReDim Preserve sNumbers(i)
                sNumbers(i) = sTmpNumber.Substring(0, 1)
                sTmpNumber = sTmpNumber.Remove(0, 1)
                i = i + 1
            Loop

            '=MOD(10-MOD(SUM(Q21;O21;M21;K21;I21;G21)*3+Sum(P21;N21;L21;J21;H21;F21);10);10)
            iSum = (Integer.Parse(sNumbers(14)) + Integer.Parse(sNumbers(12)) + Integer.Parse(sNumbers(10)) + Integer.Parse(sNumbers(8)) + Integer.Parse(sNumbers(6)) + 7) * 3 'previous was:  + Integer.Parse(sNumbers(4)) + Integer.Parse(sNumbers(2))) * 3
            iSum = iSum + Integer.Parse(sNumbers(13)) + Integer.Parse(sNumbers(11)) + Integer.Parse(sNumbers(9)) + Integer.Parse(sNumbers(7)) + 11 'previous was: + Integer.Parse(sNumbers(5)) + Integer.Parse(sNumbers(3)) + Integer.Parse(sNumbers(1))
            iSum = (10 - (iSum Mod 10)) Mod 10

            sRetVal = sFirstSet & sNumbers(6) & sNumbers(7) & sNumbers(8) & sNumbers(9) & sNumbers(10) & sNumbers(11) & sNumbers(12) & sNumbers(13) & sNumbers(14) & iSum.ToString

        Catch ex As Exception
            MsgBox(ex.Message, MsgBoxStyle.Exclamation, "Error!")
        End Try

        Return sRetVal
    End Function

    Protected Overrides Sub Finalize()
        MyBase.Finalize()
    End Sub
End Class

ModMain.vb

Module ModMain
    'declare variable to store your class object by the interface
    Public oBarCode As IBarCodeVer = Nothing
End Module

Form1.vb

Public Class Form1

    Private Sub CmdVerify_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CmdVerify.Click
        oBarCode.MemberShipNumber = Me.TextBox1.Text
        MsgBox(oBarCode.BarCode, MsgBoxStyle.Information, "BarCode for number: " & oBarCode.MemberShipNumber)
    End Sub


    Public Sub New()

        ' This call is required by the Windows Form Designer.
        InitializeComponent()

        ' Add any initialization after the InitializeComponent() call.
        'initilize class
         oBarCode = New TBarCodeVer
    End Sub

    Protected Overrides Sub Finalize()
        'destroy class
        oBarCode = Nothing
        MyBase.Finalize()
    End Sub
End Class

5) Compile project

The above code returns 7 for the number: 6008943507588309