How to cleanly re-install an app?

If you’re having problems with an app (e.g. it won’t activate, or doesn’t work properly, or especially if there is some remainder from a previous installation), it is always worth a try to cleanly remove the app and reinstalling it from scratch:

To manually remove an app:

  1. As always before possibly dangerous changes, backup your database and files
  • Go to the database administration tool of your choice, e.g. phpmyadmin for mysql
  • In the table oc_appconfig, find all entries having the name of the app as appid (e.g. “roundcube” or “gallery”)
  • Remove those entries
  • Find tables created by the extension (e.g. “oc_roundcube” for roundcube app), and drop them
  • In the apps directory, search for the directory with the name of the app
  • Delete that directory

To (re)install an app:

  1. If it’s an app which is included in the default owncloud installation, go to the “Apps” configuration section as administrative user; the app will have an entry there, enabling the app will download the files of the app to your installation (so the “apps” directory has to be writable by php for this method to work).
  • If it’s a custom app, or you want to install the latest version: Read the INSTALL instructions of the app (usually, extract it to the “apps” subfolder of owncloud, and then go to the “Apps” configuration section as administrative user and enable it[/list]

If you should have any problems with this description, don’t hesitate to post them here!