Just wanted to add this feature that fixed this problem for me after many attempts:
If you use SELinux (for example, Fedora), you may experience a "security context" problem on / sites / default or / sites / default / files. Therefore, even if you open it with chmod 777 (not a good idea), you will get STILL permission.
fix (first cd to sites directory):
restorecon -rv default/
I ran it locally as root.
I do not pretend to be an expert in security contexts by any stretch, but the Fedora documentation is here .
, !