Hi,
Did u selected the lower case letter on check box at Info-package level?
Are you doing this in Development or PRD system?
If u r working in Dev system edit one EMP Id name with capital letter and Restrict the edited record at filter level i,e put Emp Id in DTP filter try to load for that particular record. Check loading is successfully completed or not for that particular record or not.
As per above screenshot
Just do trial