Writing client app to connect to Exchange Server 2013 and set OOF for users on vacation

Question

I am coding an C# app that should connect to Exchange Server 2013 on-premise (Servers Location is not in our Company). I`ve got an account (User and Pass) with readonly admin-rights for now and want to read and set OutOfOffice Objects for other users. I
decide to use EWS Managed API over Autodiscovery but I am bit confuse how
I tried to connect with "service.UseDefaultCredentials = true" and read contacts -> this code works:
try
            ExchangeService _service
= new ExchangeService(ExchangeVersion.Exchange2013_SP1);
            _service.Credentials
= new WebCredentials("service.exchange",
"1234", "domain");
            _service.TraceEnabled
= true;
            _service.TraceFlags
= TraceFlags.All; _service.UseDefaultCredentials
= true;
            _service.AutodiscoverUrl("[email protected]",
RedirectionUrlValidationCallback);
            foreach
(Contact contact in _service.FindItems(WellKnownFolderName.Contacts,
new ItemView(2)))
var test = contact;
        catch
(Exception exception)
            Console.WriteLine(exception);
After that I tried the same with _service.UseDefaultCredentials = false; got error -> "The Autodiscover service couldn't be located." I am not shure if this "direct log on" is the right way, On msdn I've read about "delegate access"
and "Impersonation" (NTLM and Basic Authentication) I'am a bit confused. Can anybody help me?

Answer 1

hi,
when you set a credential, you don't have to set the UseDefaultCredentials property (it is already updated).
For autodiscover, you should try to set the property EnableScpLookup to True if you are in the Exchange domain or it is known by the current domain.
Autodiscover uses a domain query (through Active Directory) and/or a dns query (this requires a DNS register for autodiscover.domain.net) to determine the access to the autodiscover service URI.
Regards,
Désiré GOVIN Refresh IT Solutions