Error connecting via ssh. How to fix?

When connecting via ssh to an ubuntu dev, an error occurs.
Alexandr Linux-VirtualBox 4.4.0-24-generic #43-Ubuntu SMP Wed Jun 8 19:27:37 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
Connecting to servers on the Internet is fine.

Connect via localhost to itself via ssh also works.

like telnet shows that the connection is.

How to fix the connection error?
July 8th 19 at 12:11
2 answers
July 8th 19 at 12:13
You need to update PuTTY to the latest version.
July 8th 19 at 12:15
"protocol violation" - see the Protocol settings of the connection on the server and the client.

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