[Plugin: Auto Post Images (API)] "This plugin does not have a valid header"

Plugin version: 3.0.1

When activating this plugin I got a “This plugin does not have a valid header.”

This might only happen on certain server configurations. Some server set-ups are ‘picky’ about how the PHP tag is opened is my experience, and it will need a lowercase full opening to work properly.*

In auto-post-images.php in the plugin folder changing the uppercase PHP:

<?PHP
/*
Plugin Name: Auto Post Images (API)

to lowercase php:

<?php
/*
Plugin Name: Auto Post Images (API)

Fixes it.

*See also ‘short_open_tag’:
Description of core php.ini directives on php.net
and ‘Example #2 PHP Opening and Closing Tags’:
Escaping from HTML on php.net