How do i stop a user signing up twice ?

[Moto]

I want to stop users who register for my website form registering for more than one user account. What is the best way to do this?

Putting cookies on a users PC seems pointless as they can be deleted. I could store a users IP address in a database, but will that work ? Not everyone has a fixed IP address.


Thanks in advance Moto

[kabatak]

you cannot really stop a user from signing up twice. what can do is just give them a hard time signing up like having unique email requirement and email validation.

[CareBear]

cookies will deter the casual ones.. storing IP addresses long term doesn't make much sense but you could have it so that someone can't sign up more then one account every 2-4 or 6 hours for example.
You need to look how to stop the most regular users because the ones who are determined to will always find a way.
Post signup you could check for accounts that are logged into from the same IP within a few minutes/hours and manually review those.
That should take care of most of them.

[Moto]

Thanks for the feedback, I think i will try a bit of both ideas, make sign-ups hard and stop sign ups from the same IP until X time has passed

I currently have one joker signed up with 7 accounts, all diffrent email addresses but the same IP :angry2:

[ECTrimble20]

if you can implement it into your script you can stop people who try to create 2 accounts with a simple little cookie activation, like in PHP that can be done like this:

<?

//all the creation stuff above

setcookie(signedup, 1, time()+604800);
//that sets the cookie to last a week
?>

then just do an activation check:
<?

if(!$signedup) {
//let the user signup
} elseif($signedup == "1") {
echo "Sorry you've signed up within the last week";
}

?>

thats a simple little method, but combining that with an IP trace works for small time little people.



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