I get this error when trying to do anything with modules or extensions. I'm currently deleting each ones presence from the db and filesystem, but i really don't want to drop freeform_pro.

Any ideas on what i can do besides delete files?

A PHP Error was encountered

Severity: Notice

Message: Undefined index: C

Filename: addons/Addons_installer.php

Line Number: 501

1 Answer 1


Always make a backup of database and the directory. Store them in a zip file. Get the backup running and working on a local development environment, and make another backup of this working copy. This way you can always return to a known working copy.

If any of the crucial modules don't work, then verify the add-on compatibility, but you will be able to keep the production website running on the version that works.

To temporary disable all extensions in 2.8, use the
hidden config variable $config['allow_extensions'] = 'y';
and uninstall the offending extension for the time being.

When a new version of the add-on becomes available,
repeat the process (of setting up a local working version)
but prior to updating EE, first update the add-on for a smooth transition.

Troubleshooting on a lower level, does require knowledge of PHP and the system.

  • I had a WSOD when i removed 'tag-solpace' from my addons folder. I'm thinking i had a corrupted db-backup. I may have to start fresh.
    – Matt
    Mar 30, 2014 at 13:27
  • I ended up going back to 2.8.1 and slowly introducing the addons back into the folder and i discovered the issue. Thanks
    – Matt
    Mar 30, 2014 at 14:19

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