Upgrade to O365 broke EWS Autodiscover

Question

My company just moved some mailboxes into O365. This has had the unfortunate effect of breaking an application created using EWS. When attempting to call out to AutodiscoverUrl(), I am met with an error.

'The Autodiscover service couldn't be located.'

Code:

        service = new ExchangeService(ExchangeVersion.Exchange2010_SP2);
        service.UseDefaultCredentials = true;
        service.AutodiscoverUrl(mailbox, RedirectionCallback);

        private bool RedirectionCallback(string url)
        {
            return true; 
        }

I have also tried setting the URL to the following

service.Url = new Uri("https://autodiscover.MYDOMAIN.com/autodiscover/autodiscover.xml");
service.Url = new Uri("https://outlook.office365.com/EWS/Exchange.asmx");

Neither of those have resolved the issue. Does anyone know where to go from here?

Answer 1

• service.UseDefaultCredentials should be false because you need email+password(as secure string) for connect
• use latest ExchangeVersion value

• url is https://outlook.office365.com/EWS/Exchange.asmx

  public ExchangeService Connect()
  {
      var lastExchangeVersion = Enum.GetValues(typeof(ExchangeVersion)).Cast<ExchangeVersion>().ToList().Last();
      var service = new ExchangeService(lastExchangeVersion)
      {
          Url = new Uri("https://outlook.office365.com/EWS/Exchange.asmx"),
          Credentials = new NetworkCredential(_cloudEmail, _cloudPassword)
      };
      return service;
  }
  public SecureString ConvertStringToSecure(string password)
  {
      if (string.IsNullOrWhiteSpace(password)) return null;
      var result = new SecureString();
      foreach (char c in password) result.AppendChar(c);
      return result;
  }