Installing third party plugins
Official plugins and extensions reside within /zp-core/zp-extensions. You should never install third party plugins there. Instead you need to install them within the root /plugins folder.
Zenphoto plugins consist at least of one file .php. It may optionally use a folder with the same name within the plugins folder that contains files like extra functions, css files or images. Example:
plugins// (contains additional files needed by your plugin)
If you download a (third party) plugin and uncompress (unzip) it you will often have the file or the file and folder within another folder. Don't upload that folder but only its content as shown above to the /plugins folder directly. The third party plugin should now show up on the plugins tab on the backend.
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