I don't know what is happening.
I have been able to connect to the server for a couple of days without problems and suddendly I got a frozen window using putty. After that, each time I try to connect, I receive this message:
disconnected: no supported authentication methods available (server sent: publickey, gssapi-with-mic)
I am using putty and puttyagent for private key. I already have uploaded the public key to the server and I was able to connect half an hour ago.
How can I check why it is failing? I haven't change the user or password or anything.
Well...
In the end, I had to delete all my keys, upload them again and wait a half an hour more or less. I don't know what happened but now it works again.