I think Project Collection Valid Users will be a read-only group. The members of this group are determined by the members of the child groups. If you want to have another person in this group, try adding them to one of the groups within the area. Since this is similar to the administrative task you are about to do, add your user to the Project Collection Administrators Group .
Later, you assign new users to Team Projects Default Collection . Team projects are automatically assigned to the Project Collection Valid Users Group .
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