Milan.. I usually do the plugin test first and of course.. the one time I skip it.....
So the issue was with WP Security. It was not even an incompatibility setting it was a security setting. Jeeze.. Thank you guys for taking a look
Okay.. so this would work but something goes wrong. When I go to http://jilldaviscoaching.com/register-2/?membership_id=25895 I can register but then it never sends me to payment when using my test registration email. It lets me register but does not sign me up for the membership and you never got to payment.
My apologies, I searched the forums using Appointments+ and 500 error and did not get any returns, now I am seeing many posts relating to the issue. I was just too narrow in my search terms. Sorry about that.