diff --git a/displaytext.cpp b/displaytext.cpp
index b20d3bbbb..5318762e8 100644
--- a/displaytext.cpp
+++ b/displaytext.cpp
@@ -73,7 +73,8 @@ void DisplayText::insertLineSpacer(QString const& line)
   appendText (line, "#d3d3d3");
 }
 
-void DisplayText::appendText(QString const& text, QColor bg, QString const& call1, QString const& call2)
+void DisplayText::appendText(QString const& text, QColor bg,
+                             QString const& call1, QString const& call2)
 {
   auto cursor = textCursor ();
   cursor.movePosition (QTextCursor::End);
@@ -142,7 +143,9 @@ void DisplayText::appendText(QString const& text, QColor bg, QString const& call
     }
   format.setBackground (bg);
   format.clearForeground ();
-//  format.setForeground(QColor("#cc0000"));                  //For flagging LoTW users
+  if(call2.size()>0 and !m_LoTW.contains(call2)) {
+    format.setForeground(QColor("#cc0000"));  //Mark LoTW non-users
+  }
   cursor.insertText(text.mid (text_index), format);
 
   // position so viewport scrolled to left
diff --git a/displaytext.h b/displaytext.h
index 8fb1d8bd7..f19ef2c71 100644
--- a/displaytext.h
+++ b/displaytext.h
@@ -47,7 +47,6 @@ private:
   bool m_bPrincipalPrefix;
   QString appendWorkedB4(QString message, QString const& callsign, QString grid, QColor * bg,
            LogBook const& logBook, QString currentBand);
-
   QFont char_font_;
   QAction * erase_action_;
   QHash<QString, QPair<QColor, QColor>> highlighted_calls_;
@@ -62,4 +61,6 @@ private:
   QColor m_color_TxMsg;
 };
 
+  extern QHash<QString,int> m_LoTW;
+
 #endif // DISPLAYTEXT_H
diff --git a/mainwindow.cpp b/mainwindow.cpp
index bb6ad3c26..ac6c06ec8 100644
--- a/mainwindow.cpp
+++ b/mainwindow.cpp
@@ -162,6 +162,7 @@ int   fast_jhpeak {0};
 int   fast_jh2 {0};
 int narg[15];
 QVector<QColor> g_ColorTbl;
+QHash<QString,int> m_LoTW;
 
 namespace
 {
@@ -931,6 +932,32 @@ MainWindow::MainWindow(QDir const& temp_directory, bool multiple,
     ui->cbMenus->setChecked(true);
     ui->cbMenus->setChecked(false);
   }
+
+  QFile f("c:/tmp/lotw-user-activity.csv");
+  if(f.open(QIODevice::ReadOnly | QIODevice::Text)) {
+    QTextStream s(&f);
+    QString line,call;
+    int nLoTW=0;
+    int i1;
+    QDateTime now=QDateTime::currentDateTime();
+    QDateTime callDateTime;
+    // Read and process the file of Hound callers.
+    while(!s.atEnd()) {
+      line=s.readLine();
+      i1=line.indexOf(",");
+      call=line.left(i1);
+      line=line.mid(i1+1);
+      i1=line.indexOf(",");
+      callDateTime=QDateTime::fromString(line.left(i1),"yyyy-MM-dd");
+      int ndays=callDateTime.daysTo(now);
+      if(ndays < 366) {
+        nLoTW++;
+        m_LoTW[call]=ndays;
+      }
+    }
+    f.close();
+  }
+
   // this must be the last statement of constructor
   if (!m_valid) throw std::runtime_error {"Fatal initialization exception"};
 }