Disable /wp-admin/plugin-install.php

Question

How can I disable plugin upload and installation via Wordpress Admin?

Should still be able to activate/deactivate plugins in admin.

Answer 1

There is a constant you can define in wp-config.php to do this.

It will also disable the theme edit, however.

<?php
// somewhere in wp-config.php

define('DISALLOW_FILE_MODS', true);

That will remove the plugin and theme file editor (which are a terrible idea anyway) and remove the ability to install plugins and themes from the admin area.