Got an Error, Invalid or Used Product Key

Got an error FZLC0056 Invalid Unknown Product Key during installation – While activating or installing Norton Antivirus you must use the Norton Product Key during that process. Some users may face Error FZLC0056: Invalid or Unknown Product Key on their Norton product activation. To fix this error just wait for 30 minutes and then try the installation process. If the error still persists then you may need to uninstall the Norton and reinstall the product from start from the official website



To troubleshoot this error, follow these methods.


Error LFZC0056: Invalid or Unknown Product Key is due to internet issue or delay in the installation process. When you first see this error then wait for some time atleast 30 minutes to get this error fixed automatically by the Norton side. If the error is not fixed then go for other steps.


Close all the running applications and the internet browser on your computer and click on the restart button of your computer for restarting the computer system. Once your device restarted and back to login screen, check whether error LFZC0056: Invalid or Unknown Norton Product Key is still there or not. If the error is not there then you can enjoy your Norton subscription. Otherwise, you can try other methods to call our technician for support at


The Norton license you have purchased has been showing the error code while installation then you can try to Uninstall the Norton and reinstall it back on the computer.


  • To uninstall Norton on your computer, click on Start button at the bottom-left corner.
  • Go to the Control Panel from the pop-up menu.
  • Choose the view type Control Panel to be Category View.
  • Click on Uninstall a Program under the Programs.
  • A list of all the installed applications will appear on your computer screen.
  • Navigate to the Norton software you wish to remove and right-click on it.
  • Choose uninstall or remove from the options.
  • When prompted for permission click yes uninstall.
  • Restart the computer when the Norton is completely removed.


  • You can install Norton either using CD or Download is from Web.
  • You will get Norton License Key along with Norton Secure Product Key after the successful purchase.
  • Once you have the Norton product, find the Norton Product Key and then follow the further steps.
  • In case of online purchase, check the Email that you received after the Norton license purchase. You Norton Product Key will be in that email along with other information of your subscription.
  • In case of CD from a retail store, open the box, a retail card will be inside the box. On that retail, card you Product Key will be there.
  • Download the installation file by clicking on the download link or insert the CD in your computer to run the installer.
  • Once the download is done, double-click on the file to start the installation.
  • On the first screen of your Norton installer, choose the language and country. Click Next.
  • Then enter your Norton Product Key and click Next. This step will activate the Norton subscription your device
  • Choose the location where you wish to save the Norton software.
  • Once you successfully install and activate the Norton license you can protect the device from various threats.


  • Norton Error Message “The Product Key Could Not Be Verified At This Time”
  • Norton account setup
  • Norton Error FZLC0055 “Key code cannot be used”
  • Restore Norton
  • Find my Norton Product Key

You can fix these issues by following these steps too. If the error still persists even after following these step then contact support for assistance regarding your error. Call us at our toll-free number to talk to a technician to help you fix the error.

Get error FZLC0056 Invalid Unknown Product Key and Norton setup UK at

When the above process is finished then you need to follow the instructions displaying on the screen to reinstall the product. In case you are facing issues while reinstalling your version of the product then you may contact Norton Support for help. Also, visit us at for the advanced troubleshooting steps and to download the guide online.

FAQs –

  • How to install Norton repair tool
  • How to troubleshoot Norton error 8504
  • What are the Norton problems today
  • Error while opening Norton internet security.
  • What is the difference between windows 10 and Norton internet security
  • Error: Norton will not open
  • How to resolve Norton security installation problems
  • Error: Norton disappeared windows 10
  • Error: Norton icon missing from desktop
  • How to install Norton security on Mac
  • Unable to find the Norton antivirus on desktop
  • Issues with the Norton login credentials
  • What is Norton remove and reinstall tool
  • How to remove Norton from Windows 10
  • Issues with the Norton com link

You only need to visit to fix all your issues.

Garry, he has been making people aware of security threats from so long, to make the internet a safer place to browse on. His passion is to write about Cybersecurity, Antivirus, malware, social networking, internet, and new media. He writes for Norton security products at



Leave a Reply

Your email address will not be published. Required fields are marked * is an independent support provider on On-Demand Remote Technical Services For Norton Security products. Use of Norton Name, logo, trademarks, Product Images is only for reference and in no way intended to suggest that Technology has any business association with Norton. Norton trademarks, Names, logo and Images are the property of their respective owners disclaims any ownership in such conditions.