I am facing this weird behavior inside our sharepoint on-premises 2013 farm, regarding that invitation emails (which should be sent when users add another users to a security group) will not be sent to users, unless the user who invited them have at-least "Manage Permission" permission level assign to him through a sharepoint security group.
For example. i got this scenario:-
but if user with contribute permission, add another user to a security group, then the user will be added correctly, but no invitation email will be sent, even if the user checked the "Send an email invitation" checkbox:-
so currently i am trying to figure out which point should guide me to the path to solve the problem:-
is this a problem or a setting within sharepoint farm?
is this a problem or a setting within exchnage server ?
is this something sharepoint have by design ? so it will not allow invitation emails to be sent unless the user who invited others have at-least "Manage Permission" assigned to him ? if the answer if yes, then why sharepoint showed the "Send an email invitation" checkbox to unauthorized users? and let us to face the troubles with our customers ??