Access Denied on Drupal 8 image styles despite correct permissions I have a functioning D8 site that has recently started displaying odd behaviour. Image styles are no longer generating correctly.

The sample.png used in the image styles config page generates fine (including if I delete the file manually from the image styles dir).

I have recursively set 0775 (dirs) and 0664 (files) to the entire sites/default/files directory, but the error persists. Error log just shows "access denied" - nothing more informative.

Drupal version is 8.1.9.

Any ideas? The site looks pretty lame right now!
I have had issues in the past where derivatives weren't generating correctly intermittently and it was due to disc space running out.  When logs were purged the image derivatives would generate, but otherwise, the server was running out of space.  So that's one idea.