Great input, thanks, that would solve one worry.

What happens if I implement this and have duplicate users on the same e-mail already in my system? Does it only affect new users when registring - and maybe when changing e-mail on an existing account?

BTW is there any way to get a password retrieval using the e-mail address. A common problem with users forgetting their user name when they maybe don´t login every day. I believe there is some security reason behind this in DNN?

/Sölve

I don't know what would happen if you change the setting in web.config to require unique email, after it has already been functioning with that requirement set to false.  My guess is that it would work and that the change would only apply to new users, but that would need to be tested.  You'd probably want to search for and expunge pre-existing users with duplicate emails as well.

The error which comes up if someone tries to create a new account when one with the same email already exists (when that requirement is set to true in web.config) is:

"A user already exists for the email address specified.  Please login using the registered account of that email address."

Our testing indicates that if the email address is changed for that pre-existing user, then a new user can be created with that address, as one would expect.

The Question and Answer functionality in web.config isn't implemented, so that can't be used to locate a username.  There is at least one third-party module for this, which I have used successfully in the past.  However I haven't tried it with any version of DNN 3 or 4.  The module I used is the Forgotten User module by Spohn Software.  I just took a look at their site, it's a free module and it mentions that it works with DNN 2x and 3x versions.  Check it out here:  http://www.spohnsoftware.com/Default.aspx?tabid=254  Most DNN3 modules work with DNN4, however, the latest DNN 4.3.2 makes significant changes to users and profiles so it would be wise to test first, or ask Spohn.  If you can confirm it works on 4.3.2 please reply to this post to let us know!

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Shane Miller

I have a few installs where I had unique emails toggled. It does not seem to affect anything, only new registrations.

It might also complain if you try to change any of your registration info, i.e. city, state. It may detect a duplicate email and want you to change it.

The problem stems from "send password" requiring you to enter your username, where it should be their email address. Most likely people forget their usernames more than their passwords. We get a LOT of duplicate accounts due to this. I wonder if this feature request is in the gemini...

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Jason Honingford - Web & Software Developer
www.PortVista.com