As pugdog mentioned to me a few weeks ago...it is best to set up error checking early in the submission process, like at the point that the user submits a link. You should add lc codes in the add.cgi and modify.cgi if you are not going to be using the user.cgi to have users first register to your site to add links. There are email address checking codes in the user.cgi script that you could use in the above mentioned scripts as well as in the nph-email.cgi as a double error check measure.

Regards,

Eliot Lee