diff --git a/C4/Form/MessagingPreferences.pm b/C4/Form/MessagingPreferences.pm
index cbee804ad0..b98015f855 100644
--- a/C4/Form/MessagingPreferences.pm
+++ b/C4/Form/MessagingPreferences.pm
@@ -81,11 +81,11 @@ sub handle_form_action {
                         message_attribute_id    => $option->{'message_attribute_id'} };
         
         # find the desired transports
-        @{$updater->{'message_transport_types'}} = $query->param( $option->{'message_attribute_id'} );
+        @{$updater->{'message_transport_types'}} = $query->multi_param( $option->{'message_attribute_id'} );
         next OPTION unless $updater->{'message_transport_types'};
 
         if ( $option->{'has_digest'} ) {
-            if ( List::Util::first { $_ == $option->{'message_attribute_id'} } $query->param( 'digest' ) ) {
+            if ( List::Util::first { $_ == $option->{'message_attribute_id'} } $query->multi_param( 'digest' ) ) {
                 $updater->{'wants_digest'} = 1;
             }
         }
diff --git a/admin/branches.pl b/admin/branches.pl
index 3626b67cc1..abe3e5a749 100755
--- a/admin/branches.pl
+++ b/admin/branches.pl
@@ -87,7 +87,7 @@ if ( $op eq 'add_form' ) {
     if ($is_a_modif) {
         my $library = Koha::Libraries->find($branchcode);
         for my $field (@fields) {
-            $library->$field( $input->param($field) );
+            $library->$field( scalar $input->param($field) );
         }
         $library->update_categories( \@categories );
 
@@ -168,9 +168,9 @@ if ( $op eq 'add_form' ) {
     if ($is_a_modif) {
         my $category = Koha::LibraryCategories->find($categorycode);
         for my $field (@fields) {
-            $category->$field( $input->param($field) );
+            $category->$field( scalar $input->param($field) );
         }
-        $category->show_in_pulldown( $input->param('show_in_pulldown') eq 'on' );
+        $category->show_in_pulldown( scalar $input->param('show_in_pulldown') eq 'on' );
         eval { $category->store; };
         if ($@) {
             push @messages, { type => 'alert', code => 'error_on_update_category' };
@@ -183,7 +183,7 @@ if ( $op eq 'add_form' ) {
                 ( map { $_ => scalar $input->param($_) || undef } @fields )
             }
         );
-        $category->show_in_pulldown( $input->param('show_in_pulldown') eq 'on' );
+        $category->show_in_pulldown( scalar $input->param('show_in_pulldown') eq 'on' );
         eval { $category->store; };
         if ($@) {
             push @messages, { type => 'alert', code => 'error_on_insert_category' };
diff --git a/admin/patron-attr-types.pl b/admin/patron-attr-types.pl
index c99394b59a..ceb1184ba3 100755
--- a/admin/patron-attr-types.pl
+++ b/admin/patron-attr-types.pl
@@ -166,8 +166,8 @@ sub add_update_attribute_type {
     $attr_type->authorised_value_category($authorised_value_category);
     my $display_checkout = $input->param('display_checkout');
     $attr_type->display_checkout($display_checkout);
-    $attr_type->category_code($input->param('category_code'));
-    $attr_type->class($input->param('class'));
+    $attr_type->category_code(scalar $input->param('category_code'));
+    $attr_type->class(scalar $input->param('class'));
     my @branches = $input->multi_param('branches');
     $attr_type->branches( \@branches );
 
diff --git a/catalogue/image.pl b/catalogue/image.pl
index f347640652..3d95b0584c 100755
--- a/catalogue/image.pl
+++ b/catalogue/image.pl
@@ -64,7 +64,7 @@ if ( C4::Context->preference("LocalCoverImages") ) {
         $imagenumber = $data->param('imagenumber');
     }
     elsif ( defined $data->param('biblionumber') ) {
-        my @imagenumbers = ListImagesForBiblio( $data->param('biblionumber') );
+        my @imagenumbers = ListImagesForBiblio( $data->multi_param('biblionumber') );
         if (@imagenumbers) {
             $imagenumber = $imagenumbers[0];
         }
diff --git a/circ/circulation.pl b/circ/circulation.pl
index e31c7c5bec..66b3dcfee0 100755
--- a/circ/circulation.pl
+++ b/circ/circulation.pl
@@ -184,7 +184,7 @@ if ( @$barcodes ) {
         $stickyduedate  = $query->param('stickyduedate');
         $duedatespec    = $query->param('duedatespec');
     }
-    $session->param('auto_renew', $query->param('auto_renew'));
+    $session->param('auto_renew', scalar $query->param('auto_renew'));
 }
 else {
     $session->clear('auto_renew');
diff --git a/svc/config/systempreferences b/svc/config/systempreferences
index 021db3c898..01cd782dc4 100755
--- a/svc/config/systempreferences
+++ b/svc/config/systempreferences
@@ -94,7 +94,7 @@ sub set_preferences {
 
             next if ( !defined( $pref ) );
 
-            my $value = join( ',', $query->param( $param ) );
+            my $value = join( ',', $query->multi_param( $param ) );
 
             C4::Context->set_preference( $pref, $value );
         }
diff --git a/tools/marc_modification_templates.pl b/tools/marc_modification_templates.pl
index 10589e4141..3689684c51 100755
--- a/tools/marc_modification_templates.pl
+++ b/tools/marc_modification_templates.pl
@@ -42,7 +42,7 @@ my ($template, $loggedinuser, $cookie)
 
 if ( $op eq "create_template" ) {
   $template_id = '' unless $cgi->param('duplicate_current_template');
-  $template_id = AddModificationTemplate( $cgi->param('template_name'), $template_id );
+  $template_id = AddModificationTemplate( scalar $cgi->param('template_name'), $template_id );
 
 } elsif ( $op eq "delete_template" ) {
 
@@ -103,11 +103,11 @@ if ( $op eq "create_template" ) {
     }
 
 } elsif ( $op eq "delete_action" ) {
-  DelModificationTemplateAction( $cgi->param('mmta_id') );
+  DelModificationTemplateAction( scalar $cgi->param('mmta_id') );
 
 } elsif ( $op eq "move_action" ) {
 
-  MoveModificationTemplateAction( $cgi->param('mmta_id'), $cgi->param('where') );
+  MoveModificationTemplateAction( scalar $cgi->param('mmta_id'), scalar $cgi->param('where') );
 
 }