Alex T⚜️ I spoke too soon. New members cannot log in to complete the create profile. I've had to put my site in maintenance mode since last night.

Could you please describe the problem in the details ?

I'm always a fan of videos to show what is going on. A member joins, 500 error, confirms email, then never gets into the site after that to create a profile.

Thank you for the details, HTTP 500 Error means that there is some server error, could you please check your server error log files, particularly php error log? it maybe problem is some 3rd-party module.