This error message indicates that the passphrase you entered is incorrect and that the private key file could not be read.
It also possible that the key file has been damaged, but this is unlikely.
This error results in an authentication failure (see Section Authentication Failure) and disconnecting (see Section Disconnection). Click OK on both error dialogs to continue.
Try to connect again. If this error is repeated, upload your public key to the remote host computer again. For more information on this procedure, see Section Uploading Your Public Key.