Since version 3.2, WordPress requires PHP version 5.2.4 or higher to run smoothly. Anything short of this will leave you stuck with the HTTP error. Some hosts use older versions of PHP, which means no matter what you try, you can’t upload images to the WordPress media library.
What to do? First, check with your host to ensure they are using PHP version 5.2.4 and above. Alternatively, you can join millions of other website owners at Hostinger, which offers the latest stable PHP version upon release. Opt for the dedicated WordPress plans for the best experience.