Drill-down bug? grouping by date

Hi all,

I've a problem when I open a .rpt in crystal reports viewer 2011. Everywhere I can drill-down, but not if there is a group with dates. Then I can't drill-down. But in viewer version 2008 it does well.

I hope somebody can help me with this problem if it is neccesary that i upload a testfile i can.

Sorry for my english,

kind regards fer