SFTP Private Key Compatibility

BC Version 3 or 4, Pro Edition only

The default private key format used by OpenSSH 7.8+ is not compatible with Beyond Compare 4.3.7 or older.

Error

SFTP connections using an OpenSSH format key fail with the errors:
No more authentication methods available Connection failed: Connection lost (error code is 10058)

Identifying Key Format

OpenSSH format (incompatible) keys start with -----BEGIN OPENSSH PRIVATE KEY-----, OpenSSL format keys (compatible with older versions of Beyond Compare) start with -----BEGIN RSA PRIVATE KEY-----.

Converting Existing OpenSSH Format Keys to a Compatible Format

Windows:
Load the private key in PuttyGen, then click Save private key to save the file as a .ppk.

Mac, Linux:
cp ~/.ssh/id_rsa ~/.ssh/id_rsa.bc ssh-keygen -p -m PEM -f ~/.ssh/id_rsa.bc