Automate with Putty-SSH for 2 users

Hi,

I have automated logins to Unix boxes with Ssh - Putty combination.
Have created a Pub - Pvt key combination for the same.
Added the entry of username in "User name" box of Putty.

This works perfectly for the specified user.

I want this to happen now for another user as well, without changing the user name in above box everytime.
How can this be done?

Thanks