Hello
There doesn't seem to be an error sequence for the wrong password. I put in the wrong password and it logged me in and gave me the green box in the upper right that says: wrong password have you forgotten. But I could see the forum and create a new topic. And then when I selected a new forum to post to it gave me the white screen. Do I have something set up incorrectly?
Do you use cache plugins? I think this is a cache plugin or the password was not reset. First please make sure the forum page is excluded from your cache plugin and disable the cache plugin during all tests. Here is the topic guiding you why you should exclude wpForo from cache plugins: https://wpforo.com/community/faq/wpforo-and-cache-plugins/
The only cache mechanism in place is what our host Siteground installs by default. I think this might have occurred because I had too many windows open. But this was good education.
This was a complex of conflict with wpForo. We found other reCAPYTCHA and User Login plugins. Both are deactivated and the core wpForo alternatives are enabled.