diff --git a/src/java/davmail/imap/ImapConnection.java b/src/java/davmail/imap/ImapConnection.java
index d6507dcb..87cc36fa 100644
--- a/src/java/davmail/imap/ImapConnection.java
+++ b/src/java/davmail/imap/ImapConnection.java
@@ -230,6 +230,7 @@ public class ImapConnection extends AbstractConnection {
                                                         sendClient(commandId + " NO No message found");
                                                     } else {
                                                         while (uidRangeIterator.hasNext()) {
+                                                            DavGatewayTray.switchIcon();
                                                             ExchangeSession.Message message = uidRangeIterator.next();
                                                             handleFetch(message, uidRangeIterator.currentIndex, parameters);
                                                         }
@@ -287,6 +288,7 @@ public class ImapConnection extends AbstractConnection {
                                             String action = tokens.nextToken();
                                             String flags = tokens.nextToken();
                                             while (uidRangeIterator.hasNext()) {
+                                                DavGatewayTray.switchIcon();
                                                 ExchangeSession.Message message = uidRangeIterator.next();
                                                 updateFlags(message, action, flags);
                                                 sendClient("* " + (uidRangeIterator.currentIndex) + " FETCH (UID " + message.getImapUid() + " FLAGS (" + (message.getImapFlags()) + "))");
@@ -297,6 +299,7 @@ public class ImapConnection extends AbstractConnection {
                                                 UIDRangeIterator uidRangeIterator = new UIDRangeIterator(tokens.nextToken());
                                                 String targetName = BASE64MailboxDecoder.decode(tokens.nextToken());
                                                 while (uidRangeIterator.hasNext()) {
+                                                    DavGatewayTray.switchIcon();
                                                     ExchangeSession.Message message = uidRangeIterator.next();
                                                     session.copyMessage(message, targetName);
                                                 }
@@ -318,6 +321,7 @@ public class ImapConnection extends AbstractConnection {
                                             parameters = tokens.nextToken();
                                         }
                                         while (rangeIterator.hasNext()) {
+                                            DavGatewayTray.switchIcon();
                                             ExchangeSession.Message message = rangeIterator.next();
                                             handleFetch(message, rangeIterator.currentIndex, parameters);
                                         }
diff --git a/src/java/davmail/ui/tray/DavGatewayTray.java b/src/java/davmail/ui/tray/DavGatewayTray.java
index 07b691c2..e0f40fba 100644
--- a/src/java/davmail/ui/tray/DavGatewayTray.java
+++ b/src/java/davmail/ui/tray/DavGatewayTray.java
@@ -34,7 +34,9 @@ import java.net.URL;
  * Tray icon handler
  */
 public final class DavGatewayTray {
-    protected static final Logger LOGGER = Logger.getLogger("davmail");
+    private static final Logger LOGGER = Logger.getLogger("davmail");
+    private static final long ICON_SWITCH_MINIMUM_DELAY = 250;
+    private static long lastIconSwitch;
 
     private DavGatewayTray() {
     }
@@ -59,7 +61,10 @@ public final class DavGatewayTray {
      */
     public static void switchIcon() {
         if (davGatewayTray != null) {
-            davGatewayTray.switchIcon();
+            if (System.currentTimeMillis() - lastIconSwitch > ICON_SWITCH_MINIMUM_DELAY) {
+                davGatewayTray.switchIcon();
+                lastIconSwitch = System.currentTimeMillis();
+            }
         }
     }
 
@@ -87,7 +92,7 @@ public final class DavGatewayTray {
      * @param message text message
      * @param level   log level
      */
-    protected static void displayMessage(BundleMessage message, Level level) {
+    private static void displayMessage(BundleMessage message, Level level) {
         LOGGER.log(level, message.formatLog());
         if (davGatewayTray != null) {
             davGatewayTray.displayMessage(message.format(), level);
@@ -101,7 +106,7 @@ public final class DavGatewayTray {
      * @param e       exception
      * @param level   log level
      */
-    protected static void displayMessage(BundleMessage message, Exception e, Level level) {
+    private static void displayMessage(BundleMessage message, Exception e, Level level) {
         if (e instanceof NetworkDownException) {
             LOGGER.log(level, BundleMessage.getExceptionLogMessage(message, e));
         } else {
@@ -263,7 +268,7 @@ public final class DavGatewayTray {
      *
      * @return true on Mac OS X
      */
-    protected static boolean isOSX() {
+    private static boolean isOSX() {
         return System.getProperty("os.name").toLowerCase().startsWith("mac os x");
     }