title: Outlook, Folder EntryId changes at runtime
body: <p>I have an issue with sentfolder EntryId from Outlook.</p>
  <p>I work with sentfolder</p>
  <p>I have 2 Accounts.
  My account (dafault(Exchange)): all works perfect.</p>
  <p>The second account(additional(Exchange)) has:</p>
  <pre><code>outboxMailEntryID = 00000000A24FEAFFFFB93C47A13126365D132558010010E2685A8E0AC440B14F77F5EE5275A5000000BBA**800000**0
  sentMailEntryID = 00000000A24FEAFFFFB93C47A13126365D132558010010E2685A8E0AC440B14F77F5EE5275A5000000BBA7FF0000
  </code></pre>
  <p>At runtime the sendfolder get an other EntryId. It changes</p>
  <p>from:</p>
  <pre><code>IsOutputExtended check folder.Name = **Gesendete Elemente** folder.EntryID = 00000000A24FEAFFFFB93C47A13126365D132558018010E2685A8E0AC440B14F77F5EE5275A5000000BBA**8000000**
  </code></pre>
  <p>to:</p>
  <pre><code>IsOutputExtended check folder.Name = **Gesendete Elemente** folder.EntryID = 00000000A24FEAFFFFB93C47A13126365D132558018010E2685A8E0AC440B14F77F5EE5275A5000000BBA**8000100**
  </code></pre>
  <p>I do follows:</p>
  <pre><code>    private static bool IsOutputExtended(MAPIFolder currentFolder)
      {
        PropertyAccessor propAcc = null;
        Microsoft.Office.Interop.Outlook.Folders folders = null;
        MAPIFolder rootFlder = null;
        Store store = null;
  
        if(currentFolder == null)
          return false;
  
        try
        {
          store = currentFolder.Store;
  
          const string PR_IPM_OUTBOX_ENTRYID = &quot;http://schemas.microsoft.com/mapi/proptag/0x35E40102&quot;;
          const string PR_IPM_SENTMAIL_ENTRYID = &quot;http://schemas.microsoft.com/mapi/proptag/0x35E20102&quot;;
          
          rootFlder = store?.GetRootFolder();
          folders = rootFlder?.Folders;
  
          string sentMailEntryID = &quot;&quot;;
          string outboxMailEntryID = &quot;&quot;;
          propAcc = store?.PropertyAccessor;
  
          try
          {
            if (propAcc != null)
            {
              object entryOutbox = propAcc.GetProperty(PR_IPM_OUTBOX_ENTRYID);
              outboxMailEntryID = propAcc.BinaryToString(entryOutbox);
              object entrySend = propAcc.GetProperty(PR_IPM_SENTMAIL_ENTRYID);
              sentMailEntryID = propAcc.BinaryToString(entrySend);
            }
          }
          catch(Exception ex)
          {
            CobraMain.Logger.Warn(&quot;Error in IsOutputExtended by Check PR_IPM_OUTBOX_ENTRYID and PR_IPM_SENTMAIL_ENTRYID for &quot; + currentFolder.Name, ex);
          }
  
          if(currentFolder.EntryID == sentMailEntryID || currentFolder.EntryID == outboxMailEntryID)
            return true;
  ....
  </code></pre>
  <p>Have someone an idea what happens?</p>
  <p>Thanks.</p>