title: Access Custompropertie set by Office.js from EWS
body: <p>I have made a Outlook Addin Angular8 Application using Office.js to interact with Outlook.</p>
  <p>Everything works fine, the Addin works fine and stores a CustomPropertie to the Mailitem which can be read after reopening the Mailitem.
  In this Implementation this is a simple hashmap.</p>
  <pre><code>this.customPropertiesContainer.set('lvAppointmentServiceId', this.selfiId);
  this.customPropertiesContainer.saveAsync();
  </code></pre>
  <p>Now I want to read the Propertie in another Application using EWS to get the Mail Item.
  Here the Implementation is very complex.</p>
  <pre><code>private PropertySet getPropertySetKnown() {
      PropertySet propertySet = null;
      try {
          propertySet = new PropertySet(BasePropertySet.FirstClassProperties, getExtendedPropertyDefinition());
      } catch (Exception e1) {
          // TODO Auto-generated catch block
          e1.printStackTrace();
      }
      return propertySet;
  }
  
  private ExtendedPropertyDefinition getExtendedPropertyDefinition() throws Exception {
      ExtendedPropertyDefinition extendedPropertyDefinition = new ExtendedPropertyDefinition(
              DefaultExtendedPropertySet.PublicStrings, CATERING_JIRA_ID, MapiPropertyType.String);
      return extendedPropertyDefinition;
  }
  </code></pre>
  <hr />
  <p>Item boundItem = Item.bind(this.exchangeService, appointmentId, getPropertySetKnown());
  jiraCateringId = boundItem.getExtendedProperties().getItems().stream()
  .filter(property -&gt; property.getPropertyDefinition().getName().equals(CATERING_JIRA_ID)).findFirst()
  .orElse(null);</p>
  <hr />
  <p>Does anyone know in which DefaultExtendedPropertySet the Propertie could be found set by Office.js ?
  Is there a way to get all Propertis using EWS with no need to define an own Definition?</p>
  <p>Is there any Debug Tool in Outlook / Exchange to see the Customproperties in an Item?</p>