Sorry Dear Monks,

I have just discovered my mistake

It was because I had looked at the data in the excel file (as they were initally were, instead of looking at them in the wordpad format)

What I gave you as input file was what I copied / pasted from the data opened in excel

But when I opened in wordpad, the data were inside ""

Instead of that :

AAD;   ;CCR;365
TEC;UTF;TDE;450
TRE;   ;FTE;164
TEC;URT;TDE;687
ERT;   ;ETR;567
TEC;UGC;TDE;687
[download]

what was in reality was

"AAD";"   ";"CCR";365
"TEC";"UTF";"TDE";450
"TRE";"   ";"FTE";164
"TEC";"URT";"TDE";687
"ERT";"   ";"ETR";567
"TEC";"UGC";"TDE";687
[download]

So I have modified my code :

while (<INFILE>){
    # the /^ indicates the begining of the research for $_ ($_ is unde
+rstated here)
    my @Elements = split(/;/,$_); 
        if ($Elements[1] ne '""'){
        print OUTFILE $_;
        }
    }
[download]