I am a journal editor and would like to decline a submission. However, when I click submission, the message I get is: Failed Ajax request or invalid JSON returned. I have tried the options from similar topics as suggested by colleagues but in vain. We upgraded from OJS 184.108.40.206 to 3.1.0.
Check your PHP error log for details.
Public Knowledge Project Team
Where exactly do I check for this? I am a novice.