diff --git a/process/projects/gen_grading.pl b/process/projects/gen_grading.pl
index 6c04c57..877bb8d 100644
--- a/process/projects/gen_grading.pl
+++ b/process/projects/gen_grading.pl
@@ -35,62 +35,68 @@ sub process
 
     my $grade = Grading->new();
 
-    my @defenses;
-    # Create defenses groups
-    opendir(my $dh, "$basedir/$year/$project_id/defenses/") or croak "can't opendir $basedir/$year/$project_id/defenses/: $!";
-    for my $sout (grep { ( ! /^\./ ) && -f "$basedir/$year/$project_id/defenses/$_" } readdir($dh))
-    {	
-	my $sid;
-	($sid = $sout) =~ s/\.xml$//;
-	push @defenses, $sid;
-
-	open my $xml, "<", "$basedir/$year/$project_id/defenses/$sout" or die $!;
-	binmode $xml;
-
-	my $str;
-	$str .= $_ while (<$xml>);
-
-	my $defense = Defense->new($str);
-
-	my $ids = $defense->getIds();
-
-	my @keys = keys %$ids;
-	my $def_i = $keys[0];
-	$def_i =~ s/^(.+)g.*$/$1/;
-
-	$ids->{$def_i.'_end_$LOGIN'} = undef;
-	$ids->{$def_i.'_end_group'} = undef;
-
-	$grade->create_from_ids($sid, $ids);
-    }
-    closedir $dh;
-
-    # Create traces groups
-    opendir($dh, "$basedir/$year/$project_id/traces/") or croak "can't opendir $basedir/$year/$project_id/traces/: $!";
-    for my $dir (grep { ( ! /^\./ ) && -d "$basedir/$year/$project_id/traces/$_" } readdir($dh))
+    if (-d "$basedir/$year/$project_id/defenses/")
     {
-	next if (grep { $dir eq "defense_$_" } @defenses);
+	my @defenses;
+	# Create defenses groups
+	opendir(my $dh, "$basedir/$year/$project_id/defenses/") or croak "can't opendir $basedir/$year/$project_id/defenses/: $!";
+	for my $sout (grep { ( ! /^\./ ) && -f "$basedir/$year/$project_id/defenses/$_" } readdir($dh))
+	{	
+	    my $sid;
+	    ($sid = $sout) =~ s/\.xml$//;
+	    push @defenses, $sid;
 
-	my $ids = {};
-
-	opendir(my $dhm, "$basedir/$year/$project_id/traces/$dir") or croak "can't opendir $basedir/$year/$project_id/traces/$dir: $!";
-	for my $login (grep { ( ! /^\./ ) && -f "$basedir/$year/$project_id/traces/$dir/$_" } readdir($dhm))
-	{
-	    open my $xml, "<", "$basedir/$year/$project_id/traces/$dir/$login" or die $!;
+	    open my $xml, "<", "$basedir/$year/$project_id/defenses/$sout" or die $!;
 	    binmode $xml;
 
-	    my $trace = Trace->new($xml);
+	    my $str;
+	    $str .= $_ while (<$xml>);
 
-	    my %tids = %{ $trace->getIds() };
-	    for my $kid (keys %tids)
-	    {
-		$ids->{ $kid } = $tids{ $kid };
-	    }
+	    my $defense = Defense->new($str);
+
+	    my $ids = $defense->getIds();
+
+	    my @keys = keys %$ids;
+	    my $def_i = $keys[0];
+	    $def_i =~ s/^(.+)g.*$/$1/;
+
+	    $ids->{$def_i.'_end_$LOGIN'} = undef;
+	    $ids->{$def_i.'_end_group'} = undef;
+
+	    $grade->create_from_ids($sid, $ids);
 	}
-
-	$grade->create_from_ids($dir, $ids);
+	closedir $dh;
+    }
+
+    if (-d "$basedir/$year/$project_id/traces/")
+    {
+	# Create traces groups
+	opendir($dh, "$basedir/$year/$project_id/traces/") or croak "can't opendir $basedir/$year/$project_id/traces/: $!";
+	for my $dir (grep { ( ! /^\./ ) && -d "$basedir/$year/$project_id/traces/$_" } readdir($dh))
+	{
+	    next if (grep { $dir eq "defense_$_" } @defenses);
+
+	    my $ids = {};
+
+	    opendir(my $dhm, "$basedir/$year/$project_id/traces/$dir") or croak "can't opendir $basedir/$year/$project_id/traces/$dir: $!";
+	    for my $login (grep { ( ! /^\./ ) && -f "$basedir/$year/$project_id/traces/$dir/$_" } readdir($dhm))
+	    {
+		open my $xml, "<", "$basedir/$year/$project_id/traces/$dir/$login" or die $!;
+		binmode $xml;
+
+		my $trace = Trace->new($xml);
+
+		my %tids = %{ $trace->getIds() };
+		for my $kid (keys %tids)
+		{
+		    $ids->{ $kid } = $tids{ $kid };
+		}
+	    }
+
+	    $grade->create_from_ids($dir, $ids);
+	}
+	closedir $dh;
     }
-    closedir $dh;
 
     return $grade->toString;
 }