Nothing wrong with the dates..

Have you looked at this :
VB Code:
  1. date1 = txtMonth1 & "/" & txtDate1 & "/" & txtYr1

  2. date2 = txtMonth2 & "/" & txtDate2 & "/" & txtYr2
These are NOT dates

They are strings, thus format won't work on them.
If you wanted dates, you should've defined them as dates and enclosed the whole lot in CDate().

This means :
VB Code:
  1. MsgBox "Flights between " & Format([b]CDate(date1)[/b], "dd/mmm/yy") & " and " & Format([b]CDate(date2)[/b], "dd/mmm/yy")

  2.  
  3. datFlights.RecordSource = "SELECT * FROM tblFlight WHERE tblFlight.DDate BETWEEN #" & [b]date1[/b] & "# AND #" & [b]date2[/b] & "# ORDER BY tblFlight.DDate"
...would suffice.


Also, someone else on the forum mentioned this before and I've found it helps clear up confusions; Use dd mmm yyyy formating from the text boxes as you won't get confused (nor will the user or the database) about american or english formatting.

Regards

Vince