Is it possible to give access to just one record on the internet and allow a person to make modifications?

Here's the deal: We're starting a directory company, producing directories for small groups. A big part of it involves getting people to update their information. Ideally, we'd send an email and by clicking on the link people could get access to their own personal data and make corrections. If you've ever updated your profile on a website, that's basically what I'm looking for, but I'd love it if logged the user into their information automatically.

If this can't be done in FileMaker (and I suspect it can't), if someone knows other software (including internet software) and could direct me, that would be awesome.

If I understand you correctly, all you need is a field that is part of the profile table called "username". You then set privileges to each user (or a set of users) which gives access to records where username = Get(AccountName)

When they logon have a script that performs a search for "*" in any field and it will return only the ones that they can see (their own).

Is that what you are looking for? I know I gave a birds eye view of the process. Let me know and I can explain it more thoroughly.