Post-processing of the image failed. If this is a photo or a large image, please scale it down to 2500 pixels and upload it again.
UPDATED: June 21st, 2021
Nothing is worse than a website error. Worse and annoying. Today, while I tried to manage a client’s WordPress site, I found a WordPress 5.3 Upload error. “Ok,” I said to myself, “let us find the problem and fix it.”. The first thing I did was to look at the image properties to see its actual size. The image size is about 1900×320 (far lower than the recommendation from the inside of the error).
Hmm… Strange. Usually, I do not have this kind of problem, even if I upload big-size images (which is very rare, but anyway). Maybe we will discuss the image optimization process more and how important this is for your business website.
So, discovering this WordPress image post-processing issue, I researched it and found a quick solution. Furthermore, I found not one but two quick ways to solve this error and get everything to work again.
The first thing I did was look at the WordPress Support forum. The users from there usually find these kinds of errors quickly and come up with solutions. However, this time I was unlucky. Well, the next step was to search on Reddit, and I found a temporary solution for this problem until WordPress solved the issue:
Post-processing of the image failed. If this is a photo or a large image, please scale it down to 2500 pixels and upload it again.
To temporary solve it, you have two options:
1. Add this line to the functions.php of your theme ( or of your child theme ):
add_filter( 'big_image_size_threshold', '__return_false' );
Pay attention to the actions you make, because you can crash the entire website!
2. ( Safer ) Install the “Disable “BIG Image” Threshold” plugin, provided by Jonathan Desrosiers ( Many thanks to you, Jonathan ). You can search the plugin in your Admin Dashboard area -> Plugins, or download it from here: https://wordpress.org/plugins/disable-big-image-threshold/
