Why can’t I change my personal settings in Microsoft Dynamics CRM 2016

Question

I've set all my security roles in CRM but unable to select the Default Tab, see screenshot below. What am i missing?.

Screenshot

Answer 1

Since you selected the Default Pane based on user role it doesn't create a filtered list for the Default Tab.
Call MS devs lazy or performance aware but they just cut corners there and do not query the Pane based on your user role to filter the Tab list.