Mysterious ssh public key authentication failure? Check /var/log/secure. You will probably see a permission problem such as that your home directory cannot be group writable (which is annoying).
A simple
$ chmod g-w ~
fixed this for me.
For a simple and free (and fairly standard!) way to secure your remote desktop sessions — and without having to figure out the crazy, proprietary Microsoft security stuff — take a look at copSSH. copSSH uses a streamlined Cygwin client to setup an SSH sever on your Windows box.
I’ve recently been using copSSH and PuTTY‘s Pageant authentication agent to tunnel RDP through PuTTY/copSSH SSH connections. Works like a charm.
One gotcha: copSSH doesn’t clean-up after itself well. Consider running taskkill from time-to-time.
C:\WINDOWS\Taskkill /F /IM bash.exe /T
Or if you prefer bashing:
$ kill -9 `ps | grep ^I.*bash$ | cut -c2-9`
Accrue more than 64 zombied PTYs and you’ll find yourself locked out of the server.