Posts made by Howard Miller

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That's strange... did you turn it all the way up to 'Developer' and 'Display errors'? Have you checked your PHP / web server error logs?

There's no advertised version for Moodle 4.2. That doesn't mean that it won't work. I can't see any bug reports for 4.2 either.
Picture of Core developers Picture of Documentation writers Picture of Particularly helpful Moodlers Picture of Peer reviewers Picture of Plugin developers
Enable Debugging (all the way to Developer and 'display errors') and do it again. You should get more information.

Also, what authentication are you using? Is it doing this with manual users (e.g. your primary admin)? See https://moodle.org/mod/forum/discuss.php?d=430356