[fel64]

Are you using .8.2.1?

get_user_profile_link() doesn’t actually have any required arguments in the newest version (https://trac.bbpress.org/browser/tags/0.8.2.1/bb-includes/template-functions.php, line 1070). I can’t understand why you’d have a problem like that.

I don’t think it needs to be used in the loop. It does if you’re not going to provide arguments, but this is an error generated by PHP not bb. Any variables passed to it that would have been set in the loop but aren’t set outside it would simply be passed along, without an error, albeit unset.