Yes Sitefinity 4.x has such functionality. Under the widget section Users you will find Registration widget
and Account activation
widget. Note you may use account activation widget on the same page where is the registration form or at a separate page Registration widget->Edit->Account Activation->Confirmation page and you place the account activation widget on this page. Note you should have SMTP
configured at your server in order to send the activation e-mail.
I hope this is helpful to you. Write back if you need more help.
the Telerik team
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