Help:
At the beginning of the initial login you entered your e-mail address.
In the last item of the initial login you can choose in fine detail which institutions of Leibniz Universität may send you information by e-mail. To do so, expand the menu "Use of personal data" and remove or set the check marks. Your e-mail address is not transmitted to the institutions; instead, the institutions transmit the information to be sent to the IdM.
By setting a check mark you allow the institution to send you information by e-mail.
Examples and explanations of the individual items can be found here.