View Full Version : Norton Internet Security symError Code Stopping JS

03-25-2005, 08:46 AM
I searched and read all through this forum and Google and can't find anything on this old subject that answers my two questions.

1. Some of my users are getting blank screens where they used to see my JavaScript/HTML pages. If they do a View/Source and send me the code, it has symError code inserted by Norton/Symantec. But I have Norton Internet Security and have Ad Blocking and Popup Blocking turned on and can't get the problem to happen for me. Any ideas?

2. Symantec's website says the insertion of the code is caused by Ad Blocking being turned on. Old forum posts say it's inserted after the first occurrence of <script on a page. And that's where it's inserted on my pages, but what's causing it? I have no ads nor do I use anything Norton looks for like the word ad or banner or a gif with typical banner dimensions. When does Norton insert their code?

Thanks, Peter

03-25-2005, 09:03 AM
do you have any window.open scripts? thats usually when the time i've seen norton insert it into code, when it reads that there is some type of window.open script, it will insert it because it sees it as a potential popup

03-25-2005, 12:19 PM
i believe the solution is to do somthing like this with your JS blocks:

<script ...><\/script>

03-27-2005, 09:49 PM
I have concluded that anytime you have Norton Ad Blocking on Norton inserts their symError code into any page containing JS, but only on my complex JS pages does it cause them to crash.

The exception is that all of my pages were crashing until I removed the open.windows from them as advised above. There are no more open.windows on any of my pages, but the complex ones must have something else Norton doesn't like.

One thing I have done is taken away the mystery for (myself and) my users. On the pages that fail, I test:

if (window.symError){alert("xxx")}

and tell them what's up. In additon, I have placed the following text on my help page:

"Ad blocking software generally looks for words like "ad" or "banner" or a graphic of a size commonly used for banners or other types of ads. We have avoided these words and don't use graphics in our ads, so our calculators work even with ad blocking software turned on. The exception is Norton Internet Security (NIS).

NIS Ad Blocking affects any webpage created with JavaScript, the code we use to make our calculators run. It inserts Norton code into all of our pages, but most are simple enough that it doesn't bother them. The calculators are complex and the insertion of the Norton code causes them to fail.

If you are using NIS with Ad Blocking turned on, you will get a message telling you what the problem is. The only solution we know of is to go to the NIS screen and turn Ad Blocking off."

Thanks for your help, and should anyone having problems with Norton's insertion of their symError code I would love to receive an e-mail.


09-22-2005, 05:41 PM

We are having the same issue on our site. However, the code you propose doesn't seem to work. The if(window.symError) is not triggering when my customers access the page. Should the script be at the very bottom of the page or just after the offending code??


09-22-2005, 05:57 PM
Hi Michael,

My calculators are very complex (for me anyway!) and also in Frames. I have it at the very bottom of my Frames page. So this may not apply to your pages.


<!-- index_food.html 050805 -->

<script src="common.js"></script>

<body bgcolor="#ffffff">
<table width=556><tr><td height=50></td></tr>
Error: JavaScript or Scripting is Disabled
Our calculators are coded in the JavaScript programming language, also called scripting, and they will not work unless your browser has the capability to interpret it. We have performed a test and it appears that either your browser does not have the capability to interpret JavaScript (very unlikely), or the capability has been disabled (much more likely).
If you would like to enable this capability, we suggest that you refer to your browser's help files or search for "enable scripting" at <a href='http://www.google.com/' target='_blank' title='Link to google.com On-Line'>google.com</a>. We cannot give instructions here because they would differ depending on what browser you are using.

<script language="JavaScript">

c="<frameset cols=160,*,0,0' frameborder=no border=0 framespacing=0>";
if (scReso=="high"){c+="<frame name='ads' src='index_food_ads_high.html' scrolling=no>"}
else {c+="<frame name='ads' src='index_food_ads_low.html' scrolling=no>"}

<frame name="image" src="index_image.html" scrolling=yes>
<frame name="create" src="index_food_create.html" scrolling=no>
<frame name="data" src="index_food_data.html" scrolling=no>

<script language="Javascript">

09-22-2005, 10:35 PM
The location of the snippet was key. That did it. Thanks! :thumbsup:

09-22-2005, 11:49 PM
Try moving all of the page inside of the head and body tags. The code you have between </head> and <body> is not allowed to be there.

02-16-2006, 10:39 PM
I have found out a way to put a message to your web page viewers if they are not able to see a javascript on your page because they have some kind of ad blocker including Norton.

First of all. Before your javascript that is not being called add this javascript setting JAVA_FLAG to 0.

SCRIPT language="Javascript">
var JAVA_FLAG = 0;

Next, you will write the code that calls your javascript. Ex:

<SCRIPT language="Javascript" src="yourscript.js">

now somewhere at the top of "yourscript.js" add the code:
This will let the following javascript know if yourscript.js was called or not and if the message needs to be displayed. Finally in your file write this javascript:

<script language="Javascript">

if (JAVA_FLAG == 0) // meaning yourscript.js was not loaded
if(window.SymError) // If Norton is installed and changing page
document.write('You have Norton Internet Security or Norton '+
'Personal Firewall installed on this computer. '+
'If the results do not show up then you need to disable '+
'Ad Blocking in Norton Internet Security and then '+
'refresh this page.<BR><BR> ');
else // if Norton not installed but still no yourscript.js
document.write('You have a program installed on this computer '+
'that is blocking the javascript for the results on '+
'this page. It is most likely an ad blocking program '+
'that might be part of a security program such as '+
'<FONT COLOR="RED">Norton Internet Security</FONT> or '+
'<FONT COLOR="RED">Norton Personal Firewall</FONT> '+
'You can try disabling the ad blocking program on '+
'your computer and refreshing this page.<BR><BR>');
} // end else

// write below for both errors
document.write('If that does not work you may also have to clear the '+
'Temporary Internet Files cache for your browser. '+
'(Ex: In Internet Explorer, click on "Tools" then '+
'"Internet Options" then "Delete Files" and then '+
'refresh this page.)<BR><BR>');
} // end if


Let me know if this code has proved useful for you.

05-10-2006, 09:06 PM
Here's what worked for my pages:

I was calling an external .js file with the following code inside the <head> tags:

<script language="javascript" type="text/javascript" src="Scripts/SiteScripts.js" />

The pages worked if PopUp Blocking was turned off in NIS, but not if PopUp Blocking was on. I made the following change to my call script and now all the pages work like champs:

<script language="javascript" type="text/javascript" src="Scripts/SiteScripts.js"></script>

Hope this helps others. I racked my brain for days figuring out that little nuance.

08-09-2006, 02:57 AM
My cure or fix for Norton inserting code into my page and breaking it is no longer working as I reported on 9/22/05, above.

My users are once again getting blank, crashed Frames/JS pages.

My code:

<script language="Javascript">

Is suppose to display the error message NIS. But it stopped working.

This is the code that Norton is inserting just after </head>:

<script language="JavaScript">
function SymError()
return true;
window.onerror = SymError;
var SymRealWinOpen = window.open;
function SymWinOpen(url, name, attributes)
return (new Object());
window.open = SymWinOpen;

This is the code the are inserting at the very bottom of my code:

<script language="JavaScript">
var SymRealOnLoad;
var SymRealOnUnload;
function SymOnUnload()
window.open = SymWinOpen;
if(SymRealOnUnload != null)
function SymOnLoad()
if(SymRealOnLoad != null)
window.open = SymRealWinOpen;
SymRealOnUnload = window.onunload;
window.onunload = SymOnUnload;
SymRealOnLoad = window.onload;
window.onload = SymOnLoad;

Can anyone see why it would keep my alert message from working? It's way beyond my novice capacity.

Thanks, Peter