--- a/src/main/java/com/glavsoft/rfb/protocol/ReceiverTask.java	Fri Feb 22 16:07:03 2019 +0900
+++ b/src/main/java/com/glavsoft/rfb/protocol/ReceiverTask.java	Fri Feb 22 19:53:15 2019 +0900
@@ -141,7 +141,8 @@
                         serverCutText();
                         break;
                     default:
-                        logger.severe("Unsupported server message. Id = " + messageId);
+                        logger.fine("Unsupported server message. Id = " + messageId);
+                        continue;
                 }
             } catch (TransportException e) {
                 System.out.println(e.getMessage());
@@ -243,8 +244,13 @@
         try {
             reader.readByte(); // padding
             this.numberOfRectangles = reader.readUInt16();
-            if(numberOfRectangles != 1)
+            if(numberOfRectangles > 2) {
                 System.out.println("numberofrectangle : " + numberOfRectangles);
+                if (rfb.getViewer().getUseMulticast()){
+
+                    return; // Discard invalid packet
+                }
+            }
             while (numberOfRectangles-- > 0) {
                 FramebufferUpdateRectangle rect = new FramebufferUpdateRectangle();
                 rect.fill(reader);