Here is a terse HowTo for using putty to ssh into a remote server without using a password.

1. Download Putty installer from the Putty download page. Make sure to grab the windows “Installer”.
2. Install Putty
3. Start PuttyGen from Start -> Putty-> PuttyGen
4. Generate a new key and save it as a .ppk file without a passphrase
5. Use Putty to login to the server you want to connect to
append the public key text from PuttyGen to the text of ~/.ssh/authorized_keys Tip: Copy and paste from the PuttyGen console.
6. Create a shortcut to your .ppk file from Start -> Startup.
7. Select the .ppk shortcut from the Startup menu to start Pageant (this will happen automatically at every startup).
8. See the Pageant icon in the system tray? Right-click it and select “New session”
9. Enter username@hostname in the “Host name” field.
You will now log in automatically.

If your key is not accepted, check your file permissions. SSH is very sensitive directory and file permissions.
chmod 700 ~/.ssh
chmod 600 ~/.ssh/authorized_keys