Validating fields (?) in html login form

[kendalswife]

I apologize if this question has been asked before. I've been searching posts for 2 days and stressing over whether I should just ask the question, and now here I am. Here goes:

I'm trying to set up a custom html login form for my new customers. I'm not collecting anything too confidential, just their name, company name, phone and mailing addy and adding this to a database. I will be assigning their usernames, but I want them to choose their own password. I have a field on my form for them to enter their password, and then a field for them to confirm that password by reentering it. How do I get FileMaker to throw up a flag if those passwords do not match? I reckon it has to do with the field validation, but I'm not having any luck.

Thanks in advance for any help.

[Anatoli]

Check that in JavaScript before submit.

Create calc field in FM, which will display YES if both fields are equal, NO if not.

On response page check IF YES, then OK part of page ELSE back button ENDIF.

[Unable]

"I will be assigning their usernames, but I want them to choose their own password."

So John Alden signs up with your site and chooses the password pocahontas.

Two months later John Alden signs up with your site and chooses the password pocahontas.

These are two different people. Have you allowed for that?

Just curious. Thanks.