Select in File by Timestamp

[#1]

I am trying to select a range of data based on a timestamp. My DateRangeStart is a timestamp and sometimes I need to sort from the start of the day and other times I need to use the exact timestamp. When I use DayStart() it works, but I can't get the syntax right if I wan't to use the exact timestamp:

The following works (selects the range I am looking for):

='>=' &

      Timestamp( DayStart( DateRangeStart ),'MM/DD/YYYY h:mm:ss[.fff] TT' )

& '<=' &

      Timestamp( DayEnd( DateRangeEnd ),'MM/DD/YYYY h:mm:ss[.fff] TT' )

The following doesn't work (no filter is set):

='>=' &

      Timestamp( DateRangeStart,'MM/DD/YYYY h:mm:ss[.fff] TT' )

& '<=' &

      Timestamp( DateRangeEnd,'MM/DD/YYYY h:mm:ss[.fff] TT' )

I also tried this, but it doesn't work either (no filter is set):

='>=' &

      Timestamp( Num( DateRangeStart ),'MM/DD/YYYY h:mm:ss[.fff] TT' )

& '<=' &

      Timestamp( Num( DateRangeEnd ),'MM/DD/YYYY h:mm:ss[.fff] TT' )

[MarcoWedel]

please post sample data and app.