Конфигурация сервера ssh - input_userauth_request: неверный пользователь

У меня проблема с настройкой моего SSH-сервера, чтобы он мог входить в систему с открытым ключом без пароля.

tail -f /var/log/auth.log дает

Feb  6 14:56:06 ubuntu sshd[24654]: rexec line 26: Deprecated option RhostsAuthentication
Feb  6 14:56:28 ubuntu sshd[24654]: Invalid user mpsd from ip.ip.ip.ip
Feb  6 14:56:28 ubuntu sshd[24654]: input_userauth_request: invalid user mpsd [preauth]
Feb  6 14:56:28 ubuntu sshd[24654]: error: Received disconnect from ip.ip.ip.ip: 14: No supported authentication methods available [preauth]

Я проверил, что /home/mpsd/.ssh имеет 700, а /home/mpsd/.ssh/authorized_keys - 600 разрешений. authorized_keys содержит открытый ключ rsa, сгенерированный на моем удаленном компьютере с Windows. мой sshd_config читает

Port 22
# Use these options to restrict which interfaces/protocols sshd will bind to
#ListenAddress ::
#ListenAddress 0.0.0.0
Protocol 2

HostKey /etc/ssh/ssh_host_rsa_key
HostKey /etc/ssh/ssh_host_dsa_key
HostKey /etc/ssh/ssh_host_ecdsa_key

UsePrivilegeSeparation yes
KeyRegenerationInterval 3600
ServerKeyBits 1024
SyslogFacility AUTH
LogLevel INFO
LoginGraceTime 120
PermitRootLogin yes
StrictModes yes
RSAAuthentication yes
PubkeyAuthentication yes
AuthorizedKeysFile ~/.ssh/authorized_keys

# Don't read the user's ~/.rhosts and ~/.shosts files
IgnoreRhosts yes
RhostsRSAAuthentication no
RhostsAuthentication no
HostbasedAuthentication no
IgnoreUserKnownHosts yes

PermitEmptyPasswords yes
ChallengeResponseAuthentication no
PasswordAuthentication no

# Kerberos options
#KerberosAuthentication no
#KerberosGetAFSToken no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes

# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes

X11Forwarding yes
X11DisplayOffset 10
PrintMotd no
PrintLastLog yes
TCPKeepAlive yes
#UseLogin no

#MaxStartups 10:30:60
#Banner /etc/issue.net

# Allow client to pass locale environment variables
AcceptEnv LANG LC_*

Subsystem sftp /usr/lib/openssh/sftp-server

# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication.  Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
UsePAM no

Я не знаю, почему в сообщении говорится о недопустимом пользователе, поскольку он явно существует. Спасибо за любую помощь.