FTP - 530 error
Currently, when someone tries to connect, it immediately rejects their credentials (username and password) and states: "530 error: username or password not correct". I've tried connecting with several accounts that I know have access to the FTP server and all get the 530 error. I tried restarting the service, removing and reassigning all the users and re-propagating permissions, no go. I even set up a new account, gave it access, tried connecting, and still get the 530 error.
Network info: all ports are open. This is a server on a university network with a public-facing IP. Nothing about the network or server config has changed since February.
The only thing I can think of that changed between today and February was a power outage from a storm a couple of weeks ago. I did a disk repair and all is otherwise well. AFP, SMB, DNS, NetBoot, and Filemaker Server all work just fine. It's only the FTP service that doesn't allow connections. Any ideas aside from rebuilding the server from scratch?
Mac Mini, Mac OS X (10.6.7)