I generated an Ed25519 key pair with puttygen, and saved the private key on my computer.

When I try to authenticate with it, I get

Unable to load private key file "my_private_key.ppk" (file format error)

I checked that it really is a private key file, the file format should be correct as it it generated by puttygen.

Any ideas how to fix it ?


The version of Putty I used was too old, it did not support ed25519 at the time. With the latest version (0.70), the error is gone.

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