We were running v3.5 successfully up until a few days ago when I kicked off the 3.6 upgrade. I've done an upgrade prior with little issue.
However this time, I got into the upgrade screen as expected and move into the plugin screen. One of the plugins had an issue so I clicked 'Cancel' on screen to go back and went to rectify the issue on my end (file wise) and refreshed the upgrade page... at some point it goes to a blank page.
I tried reverting just the plugins folder back to the default one but I still get to a blank white page with a the following error:
... is currently unable to handle this request.
HTTP ERROR 500
There is no listed error in the webhosts error logs and my host Tech Support were unable to resolve the issue from their end either.
What would cause this that may be a quicker resolution, or am I better to delete the files and reload the 3.6 ones from scratch and try the upgrade all over again?
The issue stems from a change in 3.6 that removed this file. I've found it fixes issues with HSU Forums and the Flashcards plugins. I'd recommend sending a note to the plugin developer to alert them of the issue.
If it's something like HSUForum, I'd recommend finding a new forum plugin as it hasn't been updated since 2016 and only "supports" moodle 2.9