I also was having this issue.
I had tried looking in the config.php but all config was looking good, no reason for the message.
So i started looking through the folders on the server.
\Moodle\server\php
Within the above area i found php.ini
Reading this all of this explained that this is where the values are changed.
; This directive controls whether or not and where PHP will output errors, ; notices and warnings too. Error output is very useful during development, but ; it could be very dangerous in production environments. Depending on the code ; which is triggering the error, sensitive information could potentially leak ; out of your application such as database usernames and passwords or worse. ; For production environments, we recommend logging errors rather than ; sending them to STDOUT. ; Possible Values: ; Off = Do not display any errors ; stderr = Display errors to STDERR (affects only CGI/CLI binaries!) ; On or stdout = Display errors to STDOUT ; Default Value: On ; Development Value: On ; Production Value: Off ; http://php.net/display-errors display_errors = Off
This resolved my issue, i hope it works for you.
Alan