Hi,
always when i start World of Minecraft there is no server in the list and after a short time an error appears:

"Minecraft. net returned incomplete server details.
 Missing: Server IP, Server Port, User, Passcode
Do you wish to retry or quit? "

If i press retry it appears again, if I press quit the client closes.

I already tried to delete the folder + download it again, but again I cant go onto a server. This time this error appears:
"Unable to authenticate
 Your username / password may be incorrect or there are no servers to validate your login"

My username / password is correct! But if i tried to log in with an exisisting account I can't login with it again. not even on the homepage minecraft.net :((

I hope it wasnt too much text for you and i hope you can help me soon!!!