Using Adwords Auto-tagging? Searchers may see “Page Not Found” errors instead of your landing pages!

You must test actual ads or the landing pages, do not rely on the Ad Preview tool!

A client just launched their redesigned web site and their ads unknowingly were resulting in many Page Not Found errors (404 errors). Most Adwords users may not realize that the Auto Tagging feature can result in “Page Not Found” errors that are not detected using the Ad Preview Tools within Adwords. 

If searchers receive a “Page Not Found” error when they click through from your ads most will just hit the Back button and return to the search results to click on a competitor’s ad (But only after you’ve been charged for the Clicks). Those few who take the time to continue on within your site may get frustrated trying to find what they were looking for since they will not be starting from an ideal landing page. This will significantly reduce your conversion rate –  wasting many dollars in Adwords Click charges and missed business opportunities. 

Here’s the Auto-tagging issue

Auto tagging is the default method for integrating Adwords data with Google Analytics. It’s turned on by default when you create a new Adwords Account 

With auto-tagging turned on, a unique ID parameter is added to the end of your Adwords destination URLs. For example: 

If your ad (or keyword) URL is 

Then Adwords will append a parameter such as:



On some dynamically driven web sites this can cause a hiccup resulting in a Page Not Found error. 

Unfortunately most adwords advertisers rely on the ad preview features within the adwords system. However the ad preview features do not append an auto tag parameter to the URL. So the landing page can appear to load ok in the preview when it fact it fails to load correctly from the actual ads. 

True, but unfortunate, Client Story – We started working with a new retail ecommerce client not long ago whose ads were resulting in Page Not Found errors possibly for many months before we tested for it (they had been running adwords for at least two years before we began working with them). After we had their IT fix the issue their conversion rate jumped almost significantly! That error probably cost them thousands of dollars in wasted Adwords click charges and much more in missed sales opportunities. 


Video Demonstration of the Auto-Tagging Issue (about 4 minutes)


How to test for issues with Auto-tagging  

  • Append ?gclid=test or &gclid=test (if your destination URL already contains other parameters) to the end of your AdWords destination URL

Examples – 

  • Paste this modified URL into your browser’s address bar, and press Enter
  • Check the results –

If the expected landing page loads and remains loaded with no problems then you should be ok. 

  • If Landing Page Loads incorrectly –
  • If the results are anything other than the expected landing page, such as a Page Not Found error, you have a problem.

    You should consider turning off Auto-tagging at least temporality while you troubleshoot the issue.  For our clients once their web developers were made aware of the issue they were able to either fix the auto-tagging issue or switch to manual parameters (discussed in the Google help document in the For More Info section below. Google refers to this as tracking clicks manually by tagging links)

    See the link in the For More Info section to Google’s help page for instructions on how to disable Auto-Tagging and for their troubleshooting guide. 


    Request to Google – Please, if auto-tagging is turned on, then the ad preview features should add an auto-tag too!


    More Info

    Google’s Help page with a link to their troubleshooting guide

    Learn more about Page Note Found errors (404 errors) in our Video/Text article