Adding SSH private key gives error that 0644 permissions are too open I have a generated a ssh private key .key. I want to add it into my ssh in Mac to connect to a remote server, I have only known_hosts file in ~/.ssh directory.

When I try to add it using this command:

ssh-add -K ~/.ssh/myKey.ppk


I get this error:

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@         WARNING: UNPROTECTED PRIVATE KEY FILE!          @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
Permissions 0644 for '/Users/username/.ssh/myKey.ppk' are too open.
It is required that your private key files are NOT accessible by others.
This private key will be ignored.
The error message is displayed because the file permission are set such that it is readable by other users apart from the logged-in user. To overcome the error message, you will need to change the file permissions for the private key such that it is readable only by you.

To do that, run the following command in Terminal:

cd ~/.ssh ; chmod 400 myKey.ppk

This will allow only your user to read (and not write and execute) the private key file and prevent everyone else from reading, writing and executing the file.

This will take care of the error message shown to you and you should be able to add the private key file all right.