During the registration process, choose a user name or an email address and your password. From now on, these are your login details. You can use it to log in to any number of devices. The login data will continue to work even if you use a new device (smartphone, laptop...).
Important: your activation code is not a password. Your activation code can be used once and afterwards becomes invalid.
If you have given an email address, use this to log in together with your personal password.
If you have not saved an email address, log in with your user name and your personal password.
If you already have a Sdui account and can no longer log in, first navigate back to the school selection to make sure that the right school is selected.
If the login still fails, the combination of the entered username or email and password is incorrect.
At this point you need to reset your password. On the login page click on "Forgot password?"