All plugins put into mod folder gives a 'This plugin is invalid: Missing composer.json for plugin ID (PLUGIN NAME) (guid 56) ...'

When I try to upload a plugin to my Linux server where I am hosting my Elgg installation, it says it 'cannot activate' in the admin page for plugins. I have tried to fix it for a while now and want to know if anyone can help. When I try the same plugin files on my (windows) PC, the plugins work, so it isn't the plugin files. The webserver is on Ubuntu, php 7, apache2, and everything else on the site works.

  • Which Elgg version?

     

    Possible causes of your issue:

    1 - Make sure you've installed the plugin correctly:

    /mod/plugin_id/elgg-plugin.php

    You can find plugin_id in the manifext.xml (Elgg 3) and/or composer.json (Elgg 3/4)/

    Ex., 'Blog' plugin must be placed:

    /mod/blog

    because in the manifest.xml:

    <id>blog</id>

    and in the composer.json:

    "name": "elgg/blog",

    Read more on the Elgg Docs.

    The best way to install a plugin is to use composer.

     

    2 - Check the read/write permissions on /mod directory on your server.