When sending invitations via the 1KA mail server, we do not allow you to change the sender's email address, as this would automatically result in the messages being classified as 'spam' or junk mail. This would occur because the email domain (firstname.lastname@example.org) would not match the URL domain of the survey (mydomain.1KA.si/surveyname). However, it is possible to change the 'reply-to' setting of the email address.
The adjustment of the sender's email address is only possible if the invitations are sent via an external mail server (e.g. Gmail or your own server).