SSIS package will stop on breakpoint in script task written in vb but not a corresponding one in c#

Question

I have an ssis package with an existing vb script task to send emails.

I am rewriting it in c#.

The vb version works, the c# version doesn't but it doesn't fail or error either, that I can see.

If I put a breakpoint in both, when I run the package to debug, it breaks in the vb script but not the c# script.

I have included the code for each below.

They are very similar so I am wondering if there is a task setting that controls this that I am overlooking.

Thanks in advance

The vb script is as follows.

...

Public Sub Main()

    Dim htmlMessageFrom As String = Dts.Variables("SSISErrorEmailFrom").Value.ToString
    Dim htmlMessageTo As String = Dts.Variables("SSISErrorEmailTo").Value.ToString
    Dim htmlMessageSubject As String = Dts.Variables("SSISErrorEmailSubject").Value.ToString
    Dim htmlMessageBody As String = Dts.Variables("SSISErrorEmailBody").Value.ToString
    Dim SSISErrorTable As String = Dts.Variables("SSISErrorTable").Value.ToString
    Dim smtpConnectionString As String = DirectCast(Dts.Connections("SMTP Connection").AcquireConnection(Dts.Transaction), String)
    Dim smtpServer As String = "smtprelay.white01.babcockgroup.co.uk"

    htmlMessageBody = htmlMessageBody.Replace("###subject###", htmlMessageSubject)
    htmlMessageBody = htmlMessageBody.Replace("###SSISErrorTable###", SSISErrorTable)

    SendMailMessage(
  htmlMessageFrom, htmlMessageTo,
  htmlMessageSubject, htmlMessageBody,
  True, smtpServer)

    Dts.TaskResult = ScriptResults.Success

End Sub

Private Sub SendMailMessage(
ByVal From As String, ByVal SendTo As String,
ByVal Subject As String, ByVal Body As String,
ByVal IsBodyHtml As Boolean, ByVal Server As String)

    Dim htmlMessage As MailMessage
    Dim mySmtpClient As SmtpClient

    htmlMessage = New MailMessage(
From, SendTo, Subject, Body)
    htmlMessage.IsBodyHtml = IsBodyHtml

    mySmtpClient = New SmtpClient(Server)
    mySmtpClient.Credentials = CredentialCache.DefaultNetworkCredentials
    mySmtpClient.Send(htmlMessage)

End Sub

...

The c# scipt is as follows

...

    public void Main()
    {
        sendEmail();
    }

    private void sendEmail()
    {

        var noBytes = new byte[0];
        // TODO: Add your code here
        try
        {
            string SSISErrorEmailTo = Dts.Variables["SSISErrorEmailTo"].Value.ToString();
            string SSISErrorEmailFrom = Dts.Variables["SSISErrorEmailFrom"].Value.ToString();
            string SSISErrorEmailSubject = Dts.Variables["SSISErrorSubject"].Value.ToString();
            string SSISErrorEmailBody = Dts.Variables["SSISErrorEmailBody"].Value.ToString();
            string SSISErrorTable = Dts.Variables["SSISErrorTable"].Value.ToString();

            SSISErrorEmailBody.Replace("###subject###", SSISErrorEmailSubject);
            SSISErrorEmailBody.Replace("###SSISErrorTable###", SSISErrorTable);

            string SmtpServer = "smtprelay.white01.babcockgroup.co.uk"; 

            MailMessage msg = new MailMessage(SSISErrorEmailFrom, SSISErrorEmailTo, SSISErrorEmailSubject, SSISErrorEmailBody);
            msg.IsBodyHtml = true;

            SmtpClient smtpClient = new SmtpClient(SmtpServer);
            smtpClient.Credentials = CredentialCache.DefaultNetworkCredentials;
            smtpClient.Send(msg);

            Dts.TaskResult = (int)ScriptResults.Success;
            Dts.Log("OnError script completed", -1, noBytes);
        }
        catch (Exception e)
        {
            Dts.TaskResult = (int)ScriptResults.Failure;
            Dts.Log(e.InnerException.Message, -1, noBytes);
        }
    }

...