Suggest upgrading to SP3 or later for invalid certificate errors.

chrome/browser/resources/ssl/interstitial_v2.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This is the shared code for the new (Chrome 37) security interstitials. It is
 // used for both SSL interstitials and Safe Browsing interstitials.
 
 var expandedDetails = false;
 
 function setupEvents() {
@@ skipping 20 matching lines @@
   if (overridable) {
     $('proceed-link').addEventListener('click', function(event) {
       sendCommand(ssl ? CMD_PROCEED : SB_CMD_PROCEED);
     });
   } else if (!ssl) {
     $('final-paragraph').classList.add('hidden');
   }
 
   if (ssl && overridable) {
     $('proceed-link').classList.add('small-link');
-  } else {
+  } else if ($('help-link')) {
     // Overridable SSL page doesn't have this link.
     $('help-link').addEventListener('click', function(event) {
       if (ssl)
         sendCommand(CMD_HELP);
       else if (loadTimeData.getBoolean('phishing'))
         sendCommand(SB_CMD_LEARN_MORE_2);
       else
         sendCommand(SB_CMD_SHOW_DIAGNOSTIC);
     });
   }
@@ skipping 19 matching lines @@
       sendCommand(ssl ? CMD_MORE : SB_CMD_EXPANDED_SEE_MORE);
       expandedDetails = true;
     }
   });
 
   preventDefaultOnPoundLinkClicks();
   setupCheckbox();
 }
 
 document.addEventListener('DOMContentLoaded', setupEvents);