To partecipate to the study you need:
   1) Your personal card of partecipation containing username and password (usually supplied at local meetings)
   2) To be qualified to enter in the study

Point 2 is independent from technical issues, depending on ethical committees authorizations.

I you try to approach the system without the respect of points 1 and 2, you will be rejected with a FORBIDDEN message.

The below image is not correlated with the password

It informs to you that the connection is a secure connection. Just click 'Yes' to continue without problems.