Skip to content
    Moz logo Menu open Menu close
    • Products
      • Moz Pro
      • Moz Pro Home
      • Moz Local
      • Moz Local Home
      • STAT
      • Moz API
      • Moz API Home
      • Compare SEO Products
      • Moz Data
    • Free SEO Tools
      • Domain Analysis
      • Keyword Explorer
      • Link Explorer
      • Competitive Research
      • MozBar
      • More Free SEO Tools
    • Learn SEO
      • Beginner's Guide to SEO
      • SEO Learning Center
      • Moz Academy
      • MozCon
      • Webinars, Whitepapers, & Guides
    • Blog
    • Why Moz
      • Digital Marketers
      • Agency Solutions
      • Enterprise Solutions
      • Small Business Solutions
      • The Moz Story
      • New Releases
    • Log in
    • Log out
    • Products
      • Moz Pro

        Your all-in-one suite of SEO essentials.

      • Moz Local

        Raise your local SEO visibility with complete local SEO management.

      • STAT

        SERP tracking and analytics for enterprise SEO experts.

      • Moz API

        Power your SEO with our index of over 44 trillion links.

      • Compare SEO Products

        See which Moz SEO solution best meets your business needs.

      • Moz Data

        Power your SEO strategy & AI models with custom data solutions.

      Track AI Overviews in Keyword Research
      Moz Pro

      Track AI Overviews in Keyword Research

      Try it free!
    • Free SEO Tools
      • Domain Analysis

        Get top competitive SEO metrics like DA, top pages and more.

      • Keyword Explorer

        Find traffic-driving keywords with our 1.25 billion+ keyword index.

      • Link Explorer

        Explore over 40 trillion links for powerful backlink data.

      • Competitive Research

        Uncover valuable insights on your organic search competitors.

      • MozBar

        See top SEO metrics for free as you browse the web.

      • More Free SEO Tools

        Explore all the free SEO tools Moz has to offer.

      NEW Keyword Suggestions by Topic
      Moz Pro

      NEW Keyword Suggestions by Topic

      Learn more
    • Learn SEO
      • Beginner's Guide to SEO

        The #1 most popular introduction to SEO, trusted by millions.

      • SEO Learning Center

        Broaden your knowledge with SEO resources for all skill levels.

      • On-Demand Webinars

        Learn modern SEO best practices from industry experts.

      • How-To Guides

        Step-by-step guides to search success from the authority on SEO.

      • Moz Academy

        Upskill and get certified with on-demand courses & certifications.

      • MozCon

        Save on Early Bird tickets and join us in London or New York City

      Unlock flexible pricing & new endpoints
      Moz API

      Unlock flexible pricing & new endpoints

      Find your plan
    • Blog
    • Why Moz
      • Digital Marketers

        Simplify SEO tasks to save time and grow your traffic.

      • Small Business Solutions

        Uncover insights to make smarter marketing decisions in less time.

      • Agency Solutions

        Earn & keep valuable clients with unparalleled data & insights.

      • Enterprise Solutions

        Gain a competitive edge in the ever-changing world of search.

      • The Moz Story

        Moz was the first & remains the most trusted SEO company.

      • New Releases

        Get the scoop on the latest and greatest from Moz.

      Surface actionable competitive intel
      New Feature

      Surface actionable competitive intel

      Learn More
    • Log in
      • Moz Pro
      • Moz Local
      • Moz Local Dashboard
      • Moz API
      • Moz API Dashboard
      • Moz Academy
    • Avatar
      • Moz Home
      • Notifications
      • Account & Billing
      • Manage Users
      • Community Profile
      • My Q&A
      • My Videos
      • Log Out

    The Moz Q&A Forum

    • Forum
    • Questions
    • Users
    • Ask the Community

    Welcome to the Q&A Forum

    Browse the forum for helpful insights and fresh discussions about all things SEO.

    1. Home
    2. SEO Tactics
    3. Technical SEO
    4. 404 Error Pages being picked up as duplicate content

    Moz Q&A is closed.

    After more than 13 years, and tens of thousands of questions, Moz Q&A closed on 12th December 2024. Whilst we’re not completely removing the content - many posts will still be possible to view - we have locked both new posts and new replies. More details here.

    404 Error Pages being picked up as duplicate content

    Technical SEO
    5
    7
    1693
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as question
    Log in to reply
    This topic has been deleted. Only users with question management privileges can see it.
    • kfallconnect
      kfallconnect last edited by

      Hi,

      I recently noticed an increase in duplicate content, but all of the pages are 404 error pages.

      For instance, Moz site crawl says this page: https://www.allconnect.com/sc-internet/internet.html has 43 duplicates and all the duplicates are also 404 pages (https://www.allconnect.com/Coxstatic.html for instance is a duplicate of this page).

      Looking for insight on how to fix this issue, do I add an rel=canonical tag to these 60 error pages that points to the original error page?

      Thanks!

      1 Reply Last reply Reply Quote 0
      • kfallconnect
        kfallconnect @GlobeRunner last edited by

        I just did a check and you're right, even though these pages are showing up as errors to the user they are actually showing up as 200 OK, which is causing the duplicate content issue.

        Thank you!

        1 Reply Last reply Reply Quote 1
        • GlobeRunner
          GlobeRunner last edited by

          kfallconnect, if the 404 errors are being picked up as duplicate content, then most likely they're not actually showing up as 404 error pages. It's quite possible that it's a 404 error on the site (that's what the user sees) but, in fact, the server header is not displaying a 404 error. It could be showing up as a "200 OK".

          First, I would identify the pages. If the user sees an error on the page, then that's fine. Use a server header check tool to see what the response code is when someone goes to the page. You can use something like Rex Swain's HTTP header tool to check it: http://www.rexswain.com/httpview.html . If the page shows a 404 error then you should be fine, it's not duplicate content.

          If the page is showing a "200 OK" then it most likely IS duplicate content. If the page is showing an error to users but showing a '200 OK' in the server header, then that needs to be fixed.

          But if the page is showing actual content (and not an error to visitors) then you need to look at potentially using the canonical tag or removing the content on the site completely (which is preferred).

          kfallconnect 1 Reply Last reply Reply Quote 1
          • ClaytonJ
            ClaytonJ @kfallconnect last edited by

            I have not used Drupal for a couple of years, but there used to be a plugin called Fast 404 for some versions. Need to check whether suitable and if it weighs downs page speed. Zach is right if you can manually handle it do so, but if not perhaps research a plugin and research side effects.

            1 Reply Last reply Reply Quote 0
            • kfallconnect
              kfallconnect @ClaytonJ last edited by

              We run on Drupal so I'm not sure if there is a 404 plug in

              ClaytonJ 1 Reply Last reply Reply Quote 0
              • DietzenDev
                DietzenDev last edited by

                I had some issues with 404 errors as well.

                Not sure how your site is set up but I just added permanent redirects on all the 404 duplicates I was having. I didn't have as many as you so it was pretty easy to do. I'm not sure if this is the 100% correct way of doing it but it fixed my issue.

                Hope it helps!

                1 Reply Last reply Reply Quote 0
                • ClaytonJ
                  ClaytonJ last edited by

                  I am not sure of the site is wordpress but have you considered 'smart 404' plugin. Could consider adding to the site, a solution.

                  Hope that assists.

                  Regards

                  kfallconnect 1 Reply Last reply Reply Quote 0
                  • 1 / 1
                  • First post
                    Last post

                  Got a burning SEO question?

                  Subscribe to Moz Pro to gain full access to Q&A, answer questions, and ask your own.


                  Start my free trial


                  Browse Questions

                  Explore more categories

                  • Moz Tools

                    Chat with the community about the Moz tools.

                  • SEO Tactics

                    Discuss the SEO process with fellow marketers

                  • Community

                    Discuss industry events, jobs, and news!

                  • Digital Marketing

                    Chat about tactics outside of SEO

                  • Research & Trends

                    Dive into research and trends in the search industry.

                  • Support

                    Connect on product support and feature requests.

                  • See all categories

                  Related Questions

                  • znotes

                    Duplicate Content Issues with Pagination

                    Hi Moz Community, We're an eCommerce site so we have a lot of pagination issues but we were able to fix them using the rel=next and rel=prev tags. However, our pages have an option to view 60 items or 180 items at a time. This is now causing duplicate content problems when for example page 2 of the 180 item view is the same as page 4 of the 60 item view. (URL examples below) Wondering if we should just add a canonical tag going to the the main view all page to every page in the paginated series to get ride of this issue. https://www.example.com/gifts/for-the-couple?view=all&n=180&p=2 https://www.example.com/gifts/for-the-couple?view=all&n=60&p=4 Thoughts, ideas or suggestions are welcome. Thanks

                    Technical SEO | | znotes
                    0
                  • AliMac26

                    Duplicate content and 404 errors

                    I apologize in advance, but I am an SEO novice and my understanding of code is very limited. Moz has issued a lot (several hundred) of duplicate content and 404 error flags on the ecommerce site my company takes care of. For the duplicate content, some of the pages it says are duplicates don't even seem similar to me. additionally, a lot of them are static pages we embed images of size charts that we use as popups on item pages. it says these issues are high priority but how bad is this? Is this just an issue because if a page has similar content the engine spider won't know which one to index? also, what is the best way to handle these urls bringing back 404 errors? I should probably have a developer look at these issues but I wanted to ask the extremely knowledgeable Moz community before I do 🙂

                    Technical SEO | | AliMac26
                    0
                  • Taiger

                    ?_escaped_fragment_= Duplicate error in Webmaster

                    Hi I am not sure where this came from ... ?escaped_fragment= But in webmaster we are seeing hundreds of pages with this and thus webmaster is saying that we have Pages with duplicate title tags How do I fix this, or remove it. Regards T

                    Technical SEO | | Taiger
                    0
                  • tgwebmaster

                    Getting high priority issue for our xxx.com and xxx.com/home as duplicate pages and duplicate page titles can't seem to find anything that needs to be corrected, what might I be missing?

                    I am getting high priority issue for our xxx.com and xxx.com/home as reporting both duplicate pages and duplicate page titles on crawl results, I can't seem to find anything that needs to be corrected, what am I be missing?  Has anyone else had a similar issue, how was it corrected?

                    Technical SEO | | tgwebmaster
                    0
                  • Digital-DMG

                    How to deal with duplicated content on product pages?

                    Hi, I have a webshop with products with different sizes and colours. For each item I have a different URL, with almost the same content (title tag, product descriptions, etc). In order to prevent duplicated content I'am wondering what is the best way to solve this problem, keeping in mind: -Impossible to create one page/URL for each product with filters on colour and size -Impossible to rewrite the product descriptions in order to be unique I'm considering the option to canonicolize the rest of de colours/size variations, but the disadvantage is that in case the product is not in stock it disappears from the website. Looking forward to your opinions and solutions. Jeroen

                    Technical SEO | | Digital-DMG
                    0
                  • anchorwave

                    Best 404 Error Checker?

                    I have a client with a lot of 404 errors from Web Master Tools, and i have to go through and check each of the links because Some redirect to the correct page Some redirect to another url but its a 404 error Some are just 404 errors Does anyone know of a tool where i can dump all of the urls and it will tell me If the url is redirected, and to where if the page is a 404 or other error Any tips or suggestions will be really appreciated! Thanks SEO Moz'rs

                    Technical SEO | | anchorwave
                    0
                  • CPLDistribution

                    Duplicate Content issue

                    I have been asked to review an old website to an identify opportunities for increasing search engine traffic. Whilst reviewing the site I came across a strange loop. On each page there is a link to printer friendly version: http://www.websitename.co.uk/index.php?pageid=7&printfriendly=yes That page also has a link to a printer friendly version http://www.websitename.co.uk/index.php?pageid=7&printfriendly=yes&printfriendly=yes and so on and so on....... Some of these pages are being included in Google's index. I appreciate that this can't be a good thing, however, I am not 100% sure as to the extent to which it is a bad thing and the priority that should be given to getting it sorted. Just wandering what views people have on the issues this may cause?

                    Technical SEO | | CPLDistribution
                    0
                  • Leighm

                    Should there be a canonical tag on my 404 error page?

                    In my crawl diagnostics, I notice some 4xx client errors. They are appearing for pages that no longer exist, so I'm not sure what the problem is. Shouldn't they just be dealt as 404's? Anyway, on closer inspection I noticed that my 404 error page contains a canonical tag which points to the missing page. Could this be the issue? Is it a good idea to remove the canonical tag from this error page? Thanks.

                    Technical SEO | | Leighm
                    0

                  Get started with Moz Pro!

                  Unlock the power of advanced SEO tools and data-driven insights.

                  Start my free trial
                  Products
                  • Moz Pro
                  • Moz Local
                  • Moz API
                  • Moz Data
                  • STAT
                  • Product Updates
                  Moz Solutions
                  • SMB Solutions
                  • Agency Solutions
                  • Enterprise Solutions
                  • Digital Marketers
                  Free SEO Tools
                  • Domain Authority Checker
                  • Link Explorer
                  • Keyword Explorer
                  • Competitive Research
                  • Brand Authority Checker
                  • Local Citation Checker
                  • MozBar Extension
                  • MozCast
                  Resources
                  • Blog
                  • SEO Learning Center
                  • Help Hub
                  • Beginner's Guide to SEO
                  • How-to Guides
                  • Moz Academy
                  • API Docs
                  About Moz
                  • About
                  • Team
                  • Careers
                  • Contact
                  Why Moz
                  • Case Studies
                  • Testimonials
                  Get Involved
                  • Become an Affiliate
                  • MozCon
                  • Webinars
                  • Practical Marketer Series
                  • MozPod
                  Connect with us

                  Contact the Help team

                  Join our newsletter
                  Moz logo
                  © 2021 - 2025 SEOMoz, Inc., a Ziff Davis company. All rights reserved. Moz is a registered trademark of SEOMoz, Inc.
                  • Accessibility
                  • Terms of Use
                  • Privacy

                  Looks like your connection to Moz was lost, please wait while we try to reconnect.