diff --git a/src/main/java/hudson/remoting/Engine.java b/src/main/java/hudson/remoting/Engine.java
index c6880cebe..6285c14ab 100644
--- a/src/main/java/hudson/remoting/Engine.java
+++ b/src/main/java/hudson/remoting/Engine.java
@@ -302,12 +302,24 @@ public void run() {
                 Channel channel = null;
 
                 // Try available protocols.
+                boolean triedAtLeastOneProtocol = false;
                 for (JnlpProtocol protocol : protocols) {
+                    if (!protocol.isEnabled()) {
+                        events.status("Protocol " + protocol.getName() + " is not enabled, skipping");
+                        continue;
+                    }
+                    triedAtLeastOneProtocol = true;
                     events.status("Trying protocol: " + protocol.getName());
                     try {
                         channel = protocol.establishChannel(jnlpSocket, channelBuilder);
                     } catch (IOException ioe) {
-                        events.status("Protocol failed to establish channel", ioe);
+                        events.status("Protocol " + protocol.getName() + " failed to establish channel", ioe);
+                    } catch (RuntimeException e) {
+                        events.status("Protocol " + protocol.getName() + " encountered a runtime error", e);
+                    } catch (Error e) {
+                        events.status("Protocol " + protocol.getName() + " could not be completed due to an error", e);
+                    } catch (Throwable e) {
+                        events.status("Protocol " + protocol.getName() + " encountered an unexpected exception", e);
                     }
 
                     // On success do not try other protocols.
@@ -322,7 +334,12 @@ public void run() {
 
                 // If no protocol worked.
                 if (channel == null) {
-                    onConnectionRejected("None of the protocols were accepted");
+                    if (triedAtLeastOneProtocol) {
+                        onConnectionRejected("None of the protocols were accepted");
+                    } else {
+                        onConnectionRejected("None of the protocols are enabled");
+                        return; // exit
+                    }
                     continue;
                 }
 
diff --git a/src/main/java/org/jenkinsci/remoting/engine/JnlpProtocol.java b/src/main/java/org/jenkinsci/remoting/engine/JnlpProtocol.java
index 0ddfb577f..29a4d7050 100644
--- a/src/main/java/org/jenkinsci/remoting/engine/JnlpProtocol.java
+++ b/src/main/java/org/jenkinsci/remoting/engine/JnlpProtocol.java
@@ -57,6 +57,14 @@ public abstract class JnlpProtocol {
         this.events = events;
     }
 
+    /**
+     * Whether this protocol is enabled for connecting.
+     * @return {@code true} if this protocol is enabled.
+     */
+    public boolean isEnabled() {
+        return !Boolean.getBoolean(getClass().getName()+".disabled");
+    }
+
     /**
      * Get the name of the protocol.
      */