I'm running version 6.0-182037-x64 and today I discovered the splunkd service not running. I restarted it and now I can't log in successfully: I get the HTTP 402 error in the topic title.
Anybody any clues what the cause might be?
It sounds a bit like you've reverted to the free license and its trying to log in. Are you trying to hit the login page through the URL? Perhaps just try the URL:PORT of the server?
What license do you believe you are running?