Customize date time fail

Hi all! i’m working with DWA and i have a problem when i customize calendar at mail box left menu outline.

like in this picture:

it lists many the same month at month list when i click on month at the calendar.

why this happen? and how can i resolve this problem?

Thanks all.

Subject: Can you give more info?

How exactly are you doing that customization? What code are you modifying and in which form/subform?