GetRoomLists succeeds but returns no data

Question

I am calling GetRoomLists using Exchange Web Services, we are running Exchange 2010. The below code is being executed through a Console application. The call succeeds, per the XML response of "No Error", but no data is returned. We have several hundred rooms listed when you try to add one through an Outlook Appointment, so not sure why this would happen.

I've tried using both EWS DLL version 1.2 and 2.0, using default credentials or passing in credentials. I noticed after originally posting this that the response header says we are using Exchange 2012 SP2, so I tried updating my code to use that ExchangeVersion enum value, but no change in the result.

I have successfully used EWS on this Exchange server to read mailboxes, but never rooms before.

C#

        ExchangeService es = new ExchangeService(ExchangeVersion.Exchange2010);
        es.TraceFlags = TraceFlags.EwsResponse | TraceFlags.EwsRequest;
        es.TraceEnabled = true;
        es.UseDefaultCredentials = true;
        es.AutodiscoverUrl("autodiscover@example.com");
        //this collection is empty after processing
        EmailAddressCollection eac = es.GetRoomLists();

XML Trace From Web Service Request/Response

<Trace Tag="EwsRequest" Tid="9" Time="2013-03-13 20:39:41Z" Version="14.03.0032.000">
  <?xml version="1.0" encoding="utf-8"?>
  <soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages" xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
    <soap:Header>
      <t:RequestServerVersion Version="Exchange2010" />
    </soap:Header>
    <soap:Body>
      <m:GetRoomLists />
    </soap:Body>
  </soap:Envelope>
</Trace>

<Trace Tag="EwsResponse" Tid="9" Time="2013-03-13 20:39:41Z" Version="14.03.0032.000">
  <?xml version="1.0" encoding="utf-8"?>
  <s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
    <s:Header>
      <h:ServerVersionInfo MajorVersion="14" MinorVersion="2" MajorBuildNumber="328" MinorBuildNumber="9" Version="Exchange2010_SP2" xmlns:h="http://schemas.microsoft.com/exchange/services/2006/types" xmlns="http://schemas.microsoft.com/exchange/services/2006/types" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" />
    </s:Header>
    <s:Body xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
      <GetRoomListsResponse ResponseClass="Success" xmlns="http://schemas.microsoft.com/exchange/services/2006/messages">
        <ResponseCode>NoError</ResponseCode>
        <m:RoomLists xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages" />
      </GetRoomListsResponse>
    </s:Body>
  </s:Envelope>
</Trace>

MSDN Documentation on GetRoomLists: http://msdn.microsoft.com/en-us/library/dd899416(v=exchg.140).aspx

Answer 1

Well I found the cause/solution. The confusion was in that GetRoomLists does not return a list of rooms, but instead a list of a list of rooms, or a collection of "Room Lists". These are a special type of distribution list that contains a list of rooms.

As outlined here, http://social.msdn.microsoft.com/Forums/en-US/exchangesvrdevelopment/thread/4ff04c60-48c2-4a69-ab75-2383e73bfde2, you either need to setup room lists or you need to query AD and check the msExchRecipientDisplayType attribute to track down the rooms.

This link shows an example of how to write the LDAP query to return rooms: http://social.msdn.microsoft.com/Forums/en-US/exchangesvrdevelopment/thread/e2d10953-a8f9-459c-8a0e-f10c2e568b26

Code I put together for finding rooms:

private List<string> GetConfRooms(string filter)
{
    List<string> sRooms = new List<string>();

    DirectoryEntry deDomain = System.DirectoryServices.ActiveDirectory.Domain.GetComputerDomain().GetDirectoryEntry();
    DirectorySearcher dsRooms = new DirectorySearcher(deDomain);

    dsRooms.Filter = string.Format("(&(&(&(mailNickname={0}*)(objectcategory=person)(objectclass=user)(msExchRecipientDisplayType=7))))", filter);

    dsRooms.PropertiesToLoad.Add("sn");
    dsRooms.PropertiesToLoad.Add("mail");

    foreach (SearchResult sr in dsRooms.FindAll())
    {
        sRooms.Add(sr.Properties["mail"][0].ToString());
    }

    return sRooms;
}