For various reasons error screens occur which can be the result over using, for example, an invite link twice.
Is there a way to create an error page which would display a generic apology for the error with a link to the home page?
See attached
Error Pages
cavespider I can't replicate this issue at my side.
If it happens again, you can try to disable this plugin: System - Jomsocial Redirect and see how it goes.