title: Content delivery service reports "Unable to retrieve desired results."
body: <p>When testing my Tridion content delivery web service using a web browser, I can successfully get a list of the available collections by invoking "http://webservice/odata.svc/", however when I try to access one of the collections, for example; </p>
  
  <pre><code>http://webservice/odata.svc/Publications
  </code></pre>
  
  <p>I get; </p>
  
  <pre><code>&lt;message xml:lang="en-US"&gt;Unable to retrieve desired results.&lt;/message&gt;
  </code></pre>
  
  <p>or a specific item </p>
  
  <pre><code>http://webservice/odata.svc/Publications(19)
  </code></pre>
  
  <p>I get: </p>
  
  <pre><code>&lt;message xml:lang="en-US"&gt;Unable to build publication entry: 
                               Unable to retrieve desired results.&lt;/message&gt;
  </code></pre>
  
  <p>In the logs I get the following (I've removed timestamps etc. to make it a bit more readable):</p>
  
  <pre><code>ODataService - ODATA.NET: Resource retrieval: Publications
  WebContext - setCurrentClaimStore: com.tridion.ambientdata.dotnet.DotNetClaimStore@576504fa, thread: Thread-5
  ODataWebserviceHandler - Requested a OData feed/entry: Publications with type: application/atom+xml
  ODataWebserviceHandler - Setting $top to 25
  ResolverBase - Requested OData collection
  StorageManagerFactory - Loading a non cached DAO for publicationId/typeMapping/itemExtension: 0 / Query / null
  JPQLExecutor - Can not create JPAQueryDAO object
      com.tridion.broker.StorageException: No Data Access Object for Query
      at com.tridion.storage.filesystem.FSDAOFactory.getDAOForTypeMapping(FSDAOFactory.java:177) ~[cd_datalayer.jar:na]
      at com.tridion.storage.StorageManagerFactory.getOriginalDAO(StorageManagerFactory.java:450) ~[cd_datalayer.jar:na]
      at com.tridion.storage.StorageManagerFactory.getDAO(StorageManagerFactory.java:271) ~[cd_datalayer.jar:na]        
      at com.tridion.storage.StorageManagerFactory.getDefaultDAO(StorageManagerFactory.java:178) ~[cd_datalayer.jar:na]
      at com.tridion.webservices.odata.input.jpql.JPQLExecutor.&lt;init&gt;(JPQLExecutor.java:61) [cd_webservice.jar:na]
      at com.tridion.webservices.odata.input.jpql.JPQLExecutor.getExecutor(JPQLExecutor.java:103) [cd_webservice.jar:na]
      at com.tridion.webservices.odata.input.resolver.PublicationsResolver.resolveCollection(PublicationsResolver.java:34) [cd_webservice.jar:na]
      at com.tridion.webservices.odata.input.resolver.ResolverBase.resolve(ResolverBase.java:74) [cd_webservice.jar:na]
      at com.tridion.webservices.odata.input.handler.ODataFeedRenderer.renderODataFeed(ODataFeedRenderer.java:45) [cd_webservice.jar:na]
      at com.tridion.webservices.odata.input.handler.ODataWebserviceHandler.handleODataEntity(ODataWebserviceHandler.java:193) [cd_webservice.jar:na]
      at com.tridion.webservices.odata.input.handler.ODataWebserviceHandler.handleResourceRequest(ODataWebserviceHandler.java:169) [cd_webservice.jar:na]
  FilterValue - check if value: 25 is of Integer type
  FilterValue - value: 25 is Integer
  JPQLExecutor - JPAQueryDAO has not been instantiated. Probably FS storage type was used.    
  ResolverBase - Unable to build feed Unable to retrieve desired results.    
  </code></pre>
  
  <p>This message points at my storage configuration, however I have not been able to find any clear guidance in the documentation as to how it should be set up to support the web service. </p>
  
  <p>How should my storage be configured? Is it normal to expect to have a separate deployer for the service and the web site? What other issues should I be considering?</p>