It seems the problem was generated by this plugin.
WP Performance Pack
https://ww.wp.xz.cn/plugins/wp-performance-pack/
It is really good to speed up how WordPress handles translation files, but it generates an issue while uploading images.
Hi. Thanks for the answer, but this did not work. The thumbnails aren’t generated and the upload folder is the wrong one. Both in my local install and my server it generates the thumbnail URL (and the actual image URL) in 2015/10. The image does get uploaded to the uploads folder, but no thumbnails generated.
Any ideas?
Thanks
