AdvancedSearch never fires AdvancedSearchComplete event

    Public emailSearch As Outlook.Search = Nothing
    Public syncInProcess As Boolean = False


    Sub doAdvancedSearch(ByVal syncFolderPathStr As String, ByVal syncFilterStr As String)
        Try
            syncInProcess = True
            emailSearch = olApp.AdvancedSearch(syncFolderPathStr, syncFilterStr, True, "getEmails")
        Catch ex As Exception
            syncInProcess = False
            createLog("Error", "general error", , ex.Message, ex.StackTrace)
        End Try
    End Sub

    'timer event every 30 mins to check if searchCompleteEvent has not fired, force stops the search to try again
    Private Sub cleanupTimer_Tick(sender As Object, e As EventArgs) Handles cleanupTimer.Tick
         If syncInProcess Then
             createLog("Debug", "stopping email search")
             If emailSearch IsNot Nothing Then
                  createLog("Warn", "email search not nothing")
                  emailSearch.Stop()
                  createLog("Warn", "after stopping email search")
             End If
         End If
    End Sub

   'handle AdvancedSearch completing and retrieve results
   Private Sub adxOutlookEvents_AdvancedSearchComplete(sender As Object, hostObj As Object) Handles adxOutlookEvents.AdvancedSearchComplete
        Dim tableTemp As Outlook.Table = Nothing

        Try
            createLog("Debug", "thread", Thread.CurrentThread.ManagedThreadId)
            If hostObj.Tag = "getEmails" Then
                Try
                    tableTemp = emailSearch.GetTable
                    MyTable = NewRefObj(tableTemp)
                    SyncEmailsBackgroundWorker.RunWorkerAsync(MyTable) 'process returned emails
                Catch ex As Exception
                   
                Finally
                    emailSearch = Nothing
                    tableTemp = Nothing
                End Try
            End If
        Catch ex As Exception
            createLog("Error", "general error", , ex.Message, ex.StackTrace)
        End Try
    End Sub

   'stop advance search and clean variable ready to try again
    Private Sub adxOutlookEvents_AdvancedSearchStopped(sender As Object, hostObj As Object) Handles adxOutlookEvents.AdvancedSearchStopped
        Try
            If hostObj.Tag = "getEmails" Then
                Try
                    createLog("Debug", "resetting variables")
                    syncInProcess = False
                    emailSearch = Nothing
                Catch ex As Exception
                    
                End Try
            End If
        Catch ex As Exception
            createLog("Error", "general error", , ex.Message, ex.StackTrace)
        End Try
    End Sub

string advancedSearchTag = "My test advanced search in Outlook";

private void RunAdvancedSearch(Outlook._Application OutlookApp, string wordInSubject) {
    string scope = "Inbox";
    string filter = "urn:schemas:mailheader:subject LIKE '%" + wordInSubject + "%'";
    Outlook.Search advancedSearch = null;
    Outlook.MAPIFolder folderInbox = null;
    Outlook.MAPIFolder folderSentMail = null;
    Outlook.NameSpace ns = null;
    try {
        ns = OutlookApp.GetNamespace("MAPI");
        folderInbox = ns.GetDefaultFolder(Outlook.OlDefaultFolders.olFolderInbox);
        folderSentMail = ns.GetDefaultFolder(
                                        Outlook.OlDefaultFolders.olFolderSentMail);
        scope = "'" + folderInbox.FolderPath +
                                        "','" + folderSentMail.FolderPath + "'";
        advancedSearch = OutlookApp.AdvancedSearch(
                                        scope, filter, true, advancedSearchTag);
    } catch (Exception ex) {
        MessageBox.Show(ex.Message, "An eexception is thrown");
    } finally {
        if (advancedSearch != null) Marshal.ReleaseComObject(advancedSearch);
        if (folderSentMail != null) Marshal.ReleaseComObject(folderSentMail);
        if (folderInbox != null) Marshal.ReleaseComObject(folderInbox);
        if (ns != null) Marshal.ReleaseComObject(ns);
    }
}

private void adxOutlookAppEvents1_AdvancedSearchComplete(object sender, object hostObj) {
    MessageBox.Show("adxOutlookAppEvents1_AdvancedSearchComplete");
}

private void adxRibbonButton1_OnClick(object sender, IRibbonControl control, bool pressed) {
    string searchString = this.adxRibbonEditBox1.Text;
    if (!string.IsNullOrWhiteSpace(searchString)) {
        RunAdvancedSearch(this.OutlookApp, searchString);
    } else {
        MessageBox.Show("Incorrect search string");
    }
}