Attempting to use Exchange Web Services

Hi,

I am attempting to write a test application in c# that uses Exchange Web Services over TLS1.2 to connect the Exchange Server 2010 and send an email.

I have used the example downloaded from https://code.msdn.microsoft.com/Send-Email-with-Exchange-50189e57 as a starting point with minor changes to suit our Exchange configuration.

Our Exchange server is configured to use TLS 1.2

If I run the program from inside our domain it is successful but if I run it from outside then I get the following message:

Using dotnet 4.5

“The requested security protocol is not supported”

1. private void sendButton_Click(object sender, RoutedEventArgs e)
2. {
3. try
4. {
5. ExchangeService service = new ExchangeService(ExchangeVersion.Exchange2010_SP2);
6. service.Url = new Uri(ExchangeServerURI);
7. ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
8. service.Credentials = new WebCredentials(MailUserName, MailPassword);
10. EmailMessage message = new EmailMessage(service);
11. message.Subject = subjectTextbox.Text;
12. message.Body = bodyTextbox.Text;
13. message.ToRecipients.Add(recipientTextbox.Text);
14. message.Save();
16. message.SendAndSaveCopy();
18. System.Windows.MessageBox.Show("Message sent!");
19. }
20. catch(Exception ex)
21. {
22. MessageBox.Show(ex.Message);
23. }
24. }

Any help to get this working would be much appreciated,

Thanks,

John

1 Reply

Know the answer? Post it — somebody with the same question will find it here.

John Skinner10y ago
The resolution to this problem was the fact that I did not have dotnet 4.5 installed on the server i was running the test program from. I wrongfully made the assumption that it had been installed.

Once I installed it, the test program worked OK