You make reference to your being 'heavy' by which I assume you mean resource hungry and slow ?
I am sorry i was away and its pretty late replying to you.
Being honest let me say, I actually don't use anything until or unless i have a grip on it. Your provided VBA might be the perfect one but in future, if incase i needed to amend or change i ll be in trouble once again. with Formulas i am much more familiar so i wish to have hints regarding it.
Yes, I ended up for the time being with it,
in Helper Column
=MID($C356,COLUMN(A$1)*4-3,3) ( and Dragged horizontal until )
and in the ISSUES Column
=IF(AND((COUNTIFS(N$8:S355,N356,N$8:S355,">""")+COUNTIFS(N$8:S355,O356,N$8:S355,">""")+COUNTIFS(N$8:S355,P356,N$8:S355,">""")+COUNTIFS(N$8:S355,Q356,N$8:S355,">""")+COUNTIFS(N$8:S355,R356,N$8:S355,">""")+COUNTIFS(N$8:S355,S356,N$8:S355,">""")>0),COUNTIF(D$8:D355,D356)>=1),IF(A356="AllowGPV","","D-GPV"),IF(COUNTIF(D$8:D355,D356)>=1,IF(A356="AllowGP","","Dup-GP"),IF((COUNTIFS(N$8:S355,N356,N$8:S355,">""")+COUNTIFS(N$8:S355,O356,N$8:S355,">""")+COUNTIFS(N$8:S355,P356,N$8:S355,">""")+COUNTIFS(N$8:S355,Q356,N$8:S355,">""")>0),IF(A356="AllowV","","Dup-V"),"")))
its working just if i will put vouchers in 3 digits, just want more help regarding helper column function if voucher number is put in 4 digits or 2 digits pls guide