I'm having a problem using /db/rebuild. When I go to that, I enter all my possible password combinations, and none of them work. Also, as a sidenote, this asks for a "username", while all other parts of the CMS refer to a firstname, nickname, and email, but never a username.
So, I try to reset the password by /admin/security/ and when I try that, nothing happens (when I click save), but there is a response from the Ajax call - just
ERROR:There has been an error
Is there any way to fix this or debug it? It's fairly serious because it might mean that I'm locked out of my own install when my cookie expires.