I didn't see anything like this problem in the community questions.  I
downloaded the "timecard with breaks" template from the MS site.  The time-in
and time-out cells are formatted to hh:mm AM/PM.  The contents show blank
until a time is entered.  
    I added a summary schedule worksheet where I formatted the time-in and
time-out cells also to hh:mm AM/PM.  I point to each of these cells on the
different timecard sheets (ex Sammy!E11).  When there is nothing in the
individual cells, the summary cells show 12:00 AM instead of blank.  I don't
understand why this would be, and don't know how to fix it.
    I appreciate any suggestions as to how to fix this.

Thanks.