Go to Koha Administration > Global System Preferences > OPACResetPassword
Appearance on the OPAC
Once this system preference is enabled a Forgot Password link will appear on the OPAC under the login area.
Not only is this a useful function for when users forget passwords, it can also help if you are starting on a new system, or only beginning to allow users to log into accounts on the OPAC. This functionality allows borrowers to use the Forgot your password to get their login information emailed to them, without library support.