Posts made by Howard Miller

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Thanks for the comprehensive description smile

We need to get debugging working. Please make sure debugging is turned right up to Developer and you tick the box underneath to 'Display debug messages'. That *should* produce a full trace along with the error.
 
You might also consider that you are running quite an old version of 4.1. You may want to consider updating to, at least, the latest 4.1.20 to get all the latest fixes. 
Picture of Core developers Picture of Documentation writers Picture of Particularly helpful Moodlers Picture of Peer reviewers Picture of Plugin developers
I should add... there's an official Docker image for development and testing, here https://github.com/moodlehq/moodle-docker. It's not what you want but may give you a start.

There are some other images for Moodle - e.g. the Bitnami Docker images. I mention them only to caution you against using them. If you do, it would be very difficult to provide support here. We have no idea how they configure Moodle (and nor will you).