[SR-Users] Clarification on pv_www_authenticate

Hello, I would like get further information on the "pv_www_authenticate" function from auth module. For the response code "-1", which is listed as "generic error", what exactly is covered when this function returns this? Is it just everything else that isn't listed reason (invalid password, nonce expired, no credentials, etc...). On my production system, I'm seeing this as a response code on some registration requests, and just want to know what is causing this (enabling full verbose logging is a bit difficult on my production system, and want to try to replicate it on my test environment, however just need clarification on what this covers). Thank you.