diff --git a/core/tools/extender.pl b/core/tools/extender.pl
index e112c76785..4e955bcf37 100644
--- a/core/tools/extender.pl
+++ b/core/tools/extender.pl
@@ -647,7 +647,7 @@ sub unzip {
     my $archive = shift;
 
     eval 'require Archive::Zip';
-    if ( $@ ) {
+    if (! $@ ) {
         my $zip           = Archive::Zip->new();
         my $err = $zip->read($archive);
         if ( $err ) {
@@ -690,7 +690,7 @@ sub untar {
     my $compressed = ( $archive =~ /z$/i ) ? 'z' : '';
 
     eval 'require Archive::Tar';
-    if ( $@ ) {
+    if (! $@ ) {
         my $tar = Archive::Tar->new();
         my $numberOfFiles = $tar->read( $archive, $compressed );
         unless ( $numberOfFiles > 0 ) {