X2GO+Debian+SSH key - I can't log in, what's wrong?

Question

linux

There is an already configured server with ssh key authorization and a Windows 10 client machine. You need to configure x2go.
Using the key, I can easily access the server via ssh (putty, for example), but when I connect via x2go, I get a strange problem. He asks for the password for the key 5 times ( I tried it on two keys: with and without a password, the result is the same ) and eventually displays an error:

Access denied. Authentication that can continue: publickey

There is nothing in x2go server logs, I can add debug:

Jul  3 09:19:00 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:01 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:01 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:03 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:03 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:03 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:05 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:05 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:05 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:07 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:07 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:07 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:09 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:09 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:09 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:12 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:12 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:12 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:14 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:14 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:14 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:16 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:16 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:16 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:18 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:18 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:18 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:20 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:20 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:20 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:23 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:23 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:23 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:25 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:25 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:25 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:27 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:27 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:27 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:29 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:29 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:29 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp
Jul  3 09:19:31 rdp x2gocleansessions: executing external command ,,/usr/lib/x2go/x2golistsessions_sql'' with args: rdp
Jul  3 09:19:32 rdp x2golistsessions_sql: executing external command ,,x2gopath'' with args: libexec
Jul  3 09:19:32 rdp x2golistsessions_sql: executing external command ,,/usr/lib/x2go/libx2go-server-db-sqlite3-wrapper'' with args: listsessionsroot,rdp

sshd config:

PubkeyAuthentication yes
PasswordAuthentication no
PermitEmptyPasswords no
ChallengeResponseAuthentication no
UsePAM yes
X11Forwarding yes
AcceptEnv LANG LC_*
Subsystem       sftp    /usr/lib/openssh/sftp-server
PubkeyAcceptedKeyTypes=+ssh-dss

to /var/log/auth.log

Jul 3 10:26:47 rdp sshd[19747]: Received disconnect from 192.168.18.112 port 57335:11: Bye Bye [preauth]
Jul 3 10:26:47 rdp sshd[19747]: Disconnected from 192.168.18.112 port 57335 [preauth]

What might x2go lack for authorization by key?

Answer 1

After 4 hours of googling and trying, there was a problem. If you generate a key via puttyGEN, there will be no connection. Only from under linux to do.