Trouble using Putty/Windows with Ubuntu 20.4 and public key encryption

Have tried several methods to upload my public key including the “How to Upload SSH Public Keys to a DigitalOcean Team” from the “how to” guide. Have also tried setting the authorized_keys file manually with no avail. I am using Windows 11 with Putty release Release 0.74.
I also followed thus guide Both methods give the error on the putty terminal window as “server refused our key”

and Putty says "No supported authentication methods available (server sent: Public key).

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Site Moderator
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February 24, 2023

Hello @malrixon

There is something I would like to add on top of what has already been mentioned.

It is always helpful to try connecting using another client in order to determine if the issue is within the client configuration or it is local or droplet side issue.


Thank you for your response but I found the problem was with my old version of putty. I upgraded to 0.78 and that fixed the problem.

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Bobby Iliev
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February 19, 2023

Hi there,

This might also happen if you are using an incorrect username, by default you could use the root user and later on create another sudoer user.

I could also suggest following the steps here on how to connect to your Droplet with PuTTY on Windows:

Let me know how it goes!

If this is still failing, can you confirm if this is a new Droplet or an existing one that you are trying to connect to?