How to set up Ssh/Sshd for key-based login under Cygwin (Vista) with StrictModes yes

"In my experience on normal unix systems, your authorized_keys file needs to be octal permissions 600 so that only the user who created it (and root) could be able to read it to prevent other users from seeing the file. I assume it's the same in cygwin. Strict mode is just telling you to change the permissions as you found out.

So from previous experience, I'd say you were correct. As for owner, it should be the person who owns the files, probably meaning 'this user' in your context."