I changed it this way :

my $pageValidation = $fenetre3->new_ttk__frame(-padding => "20 30 5 5"
+);
$pageValidation->g_grid(-column => 0, -row => 0, -sticky => "news");
$pageValidation->configure(-height => 300, -width => 300);


my $logcontent;
my $logfrm = $pageValidation->new_ttk__frame(-padding => "5 5 5 5");
$logfrm->g_grid(-column => 1, -row => 1, -sticky => "news");
$logfrm->configure(-borderwidth => 2, -relief => "sunken", -height => 
+300, -width => 605);

$logfrm->g_grid_propagate(0);

my $loglbl = $logfrm->new_ttk__label(-textvariable => \$logcontent, -w
+raplength=>590);
$loglbl->g_grid( -column => 0, -row => 0, -sticky => "new",-padx=>0, -
+pady=>0, );
$loglbl->configure(-width=>98,);

my $s = $pageValidation->new_ttk__scrollbar(-orient => 'vertical', -co
+mmand => [$logfrm, 'yview']);
$logfrm->configure(-yscrollcommand => [$s, 'set']);

my $boutConfirmation  = $pageValidation->new_ttk__button( -text => "La
+ncer Conversion", -command => sub {lancerApplication(\$logcontent,\%g
+eneraloptions)});
$boutConfirmation->g_grid( -column => 1, -row => 3, -sticky => "sw", -
+pady => 7);

sub lancerApplication{
  my %generaloptions = %{$_[1]};
  my $optionsfile='generalOptions.txt';
  my $paramsfile='parametersForTEICorpus.txt';
  my $refgeneraloptions= \%generaloptions;
  if ($generaloptions{'externaloptions'}){
    $optionsfile=$generaloptions{'filename'};
  }
  else{
    ecrireoptgen ($_[1]);
  }
  &ma_fonction::main($optionsfile,$paramsfile,\$_[0]);
}
[download]

I have got no more the precedent error. The program opens correctly, but I still can't see the scrollbar.

Any suggestion? BTW, thanks for your answers!