In attempt to login into a ssh server using a private key in phpstorm I ran accross this error.
Keypair ‘private_key.ppk’ is corrupt or has unknown format. Only SSH2 keys in OpenSSH format or PuTTY Private Key *.ppk are supported. Error message: The cipher ‘aes256-cbc’ is required, but it is not available.
This error will not allow the “next” and “test connection” button to appear
The issue here is that the private key format is incorrect. You’ll will need to convert the private key to open ssh format. And the way to do that is
Open your private key in PuTTYGen
Top menu “Conversions”->”Export OpenSSH key”.
Save the new OpenSSH key when prompted.