Howard Miller

We have no idea how this one-click installer installed Moodle - and nor do you I assume - which is why they make it incredibly hard to help.

A 403 error is usually due to some security setting that you may have no control over. Siteground has decided that you are not a legitimate user. It's very likely something for Siteground to fix, rather than anything in Moodle.

(403 doesn't mean something isn't available- that's 404)

I've never used Edwiser but a quick Google shows that it has its own theme, which I assume you are using. Add the line in your config.php file...

$CFG->theme = 'boost';

...does that help?

Edwiser is an optional (non-core) plugin. Did you (re-) install it when you upgraded?

'moodledata' and the database IS your Moodle site. They both needed to be in place to do the upgrade. If you do other stuff then your site is going to be in an undefined state. Anything could be going wrong.

Also, I have no idea what all those COPY commands are doing in (presumably) your docker files. I recognise most of those plugins as having working 4.3 versions, so why would you be "fixing" them yourselves? 

If you don't have enough space to do a test migration then you need to get rid of some original data or go and buy a bigger disk.

The highest Moodle version you can upgrade to from 3.7 is 4.11. So, start again, and get a copy of 4.11 working properly. That's the first step.

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