I created a sub user and tried to log in myself with an incognito window in both firefox and chrome.  All i get is a mostly blank page, I get the "CRM" bar on the topk with no modules, and a white screen with gray boxes where my dashboard modules would go.  Eventually it says "Oops! Something went wrong. We were unable to load this page. Try Again"

At first i thought it may have been due to some of the permissions i set, so i made this user a "CEO" with "Admin" selected, and still the same problem.

I do think this email was tied to another account under another organization about 10 years ago, incase that may have an impact, but this is the only email address that the user has.