Hi,
I tried this on two separate machines and both worked fine!
The only change needed is to change the YYYY to yyyy:
'Distn Date From : ' &
(If NOT HasValue({?FROMDISTNDATE}) then '00/00/0000' else totext({?FROMDISTNDATE}, 'dd/MM/yyyy')) &
' Distn Date To : ' &
(If NOT HasValue({?TODISTNDATE}) then '00/00/0000' else totext({?TODISTNDATE}, 'dd/MM/yyyy'))
-Abhilash