I have a C# program that connects to my Exchange Server 2010 and is able to read every email.
I am using the microsoft.exchange.webservices.dll library.
The problem is, that this program gives back the following exception on Exchange Server 2013:
"The remote server returned an error: (501) Not Implemented."
I have no idea what's the difference between these 2 servers.
Edit: Some Code Snippets:
ExchangeVersion version = ExchangeVersion.Exchange2013;
ExchangeService service = new ExchangeService(version);
service.Credentials = new NetworkCredential("user", "pw", "domain");
service.AutodiscoverUrl("emailaddr");
and here happens the exception:
SearchFilter sf = new SearchFilter.SearchFilterCollection(LogicalOperator.And, new SearchFilter.IsEqualTo(EmailMessageSchema.IsRead, false));
FindItemsResults<Item> findResults = service.FindItems(WellKnownFolderName.Inbox, sf, new ItemView(20));
service.LoadPropertiesForItems(findResults.Items, PropertySet.FirstClassProperties);
string mailsender = item.LastModifiedName;
Finally found the problem:
There was a load balancer between exchange server and my server. I'm bridging this load balancer now -> Works perfectly