Ansys insight: Fixing Lumerical Activation errors

LitoLito Ansys Employee Posts: 4
edited February 25 in Ansys Products

The following error messages may occur when upgrading from an older version of Lumerical software. Typically it is possible to simply install the new version without manually un-installing the older version first. However, in some cases the automatic un-install fails on Windows, resulting in one of the following errors:

  • Activation failed with error code # -
  • Error: There was a problem loading the activation library. Code #
  • Internal error: -178

Try to resolved by a "clean installation".


  • Close the error message and Reboot your PC.
  • Open Windows 'Control Panel > Programs and Features', and un-install 'Ansys Lumerical' or 'Lumerical' simulation software.
  • Go to 'C:\Program Files\Lumerical\' and ensure the product/version folder (e.g. v211) has been removed. If it is still present, delete the entire folder.
  • Removed your 'product_preference.ini' files, 'C:\Users\your_username\AppData\Roaming\Lumerical\'. Or enter '%appdata%\Lumerical' on your windows explorer. See Lumerical Product Preference.ini files for more information.
  • Reboot your computer
  • Install the new version of Lumerical software on your PC.


  • Close the error message.
  • Uninstall/Remove Lumerical from your machine.
sudo yum remove Lumerical-[version].x86_64
  • Delete the installation folder.
sudo rm -R /opt/lumerical/[version] 
(deleting FDTD preference file)
rm ~/.config/Lumerical/FDTD\ Solutions.ini
  • Install the new version of Lumerical on your machine.
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