diff --git a/dev/skeletons/modMyModule.class.php b/dev/skeletons/modMyModule.class.php
index 60bc466a907..f9901feb7bd 100644
--- a/dev/skeletons/modMyModule.class.php
+++ b/dev/skeletons/modMyModule.class.php
@@ -87,10 +87,6 @@ class modMyModule extends DolibarrModules
 		// Data directories to create when module is enabled.
 		// Example: this->dirs = array("/mymodule/temp");
 		$this->dirs = array();
-		$r=0;
-
-		// Relative path to module style sheet if exists. Example: '/mymodule/css/mycss.css'.
-		//$this->style_sheet = '/mymodule/mymodule.css.php';
 
 		// Config pages. Put here list of php page, stored into mymodule/admin directory, to use to setup module.
 		$this->config_page_url = array("mysetuppage.php@mymodule");
diff --git a/htdocs/core/lib/admin.lib.php b/htdocs/core/lib/admin.lib.php
index 3883ca30144..32ce43f473e 100644
--- a/htdocs/core/lib/admin.lib.php
+++ b/htdocs/core/lib/admin.lib.php
@@ -813,7 +813,6 @@ function unActivateModule($value, $requiredby=1)
         // TODO Cannot instantiate abstract class
     	//$genericMod = new DolibarrModul($db);
         //$genericMod->name=preg_replace('/^mod/i','',$modName);
-        //$genericMod->style_sheet=1;
         //$genericMod->rights_class=strtolower(preg_replace('/^mod/i','',$modName));
         //$genericMod->const_name='MAIN_MODULE_'.strtoupper(preg_replace('/^mod/i','',$modName));
         dol_syslog("modules::unActivateModule Failed to find module file, we use generic function with name " . $modName);
diff --git a/htdocs/core/modules/DolibarrModules.class.php b/htdocs/core/modules/DolibarrModules.class.php
index 9fcb2a89f69..3ff00325bff 100644
--- a/htdocs/core/modules/DolibarrModules.class.php
+++ b/htdocs/core/modules/DolibarrModules.class.php
@@ -1293,7 +1293,7 @@ abstract class DolibarrModules
     {
     	global $conf;
 
-    	$err=0;
+    	$error=0;
     	$entity=$conf->entity;
 
     	if (is_array($this->module_parts) && ! empty($this->module_parts))
@@ -1335,15 +1335,23 @@ abstract class DolibarrModules
     			$sql.= ")";
 
     			dol_syslog(get_class($this)."::insert_const_".$key." sql=".$sql);
-    			$resql=$this->db->query($sql);
+    			$resql=$this->db->query($sql,1);
     			if (! $resql)
     			{
-    				$this->error=$this->db->lasterror();
-    				dol_syslog(get_class($this)."::insert_const_".$key." ".$this->error);
+    			    if ($this->db->lasterrno() != 'DB_ERROR_RECORD_ALREADY_EXISTS')
+    			    {
+        			    $error++;
+        				$this->error=$this->db->lasterror();
+        				dol_syslog(get_class($this)."::insert_const_".$key." ".$this->error, LOG_ERR);
+    			    }
+    			    else
+    			    {
+    			        dol_syslog(get_class($this)."::insert_const_".$key." Record already exists.", LOG_WARNING);
+    			    }
     			}
     		}
     	}
-    	return $err;
+    	return $error;
     }
 
     /**
diff --git a/htdocs/core/modules/modCashDesk.class.php b/htdocs/core/modules/modCashDesk.class.php
index 422379b9292..0abf4fd46de 100644
--- a/htdocs/core/modules/modCashDesk.class.php
+++ b/htdocs/core/modules/modCashDesk.class.php
@@ -61,9 +61,6 @@ class modCashDesk extends DolibarrModules
 		// Data directories to create when module is enabled
 		$this->dirs = array();
 
-		// Relative path to module style sheet if exists. Example: '/mymodule/mycss.css'.
-		$this->style_sheet = '';
-
 		// Config pages. Put here list of php page names stored in admmin directory used to setup module.
 		$this->config_page_url = array("cashdesk.php@cashdesk");
 
diff --git a/htdocs/core/modules/modGravatar.class.php b/htdocs/core/modules/modGravatar.class.php
index 80b83577058..2b3bbd2d561 100644
--- a/htdocs/core/modules/modGravatar.class.php
+++ b/htdocs/core/modules/modGravatar.class.php
@@ -69,9 +69,6 @@ class modGravatar extends DolibarrModules
 		$this->dirs = array();
 		$r=0;
 
-		// Relative path to module style sheet if exists. Example: '/mymodule/mycss.css'.
-		$this->style_sheet = '';
-
 		// Config pages. Put here list of php page names stored in admmin directory used to setup module.
 		$this->config_page_url = array();
 
diff --git a/htdocs/core/modules/modPaybox.class.php b/htdocs/core/modules/modPaybox.class.php
index f59d9841629..9ddc35b1475 100644
--- a/htdocs/core/modules/modPaybox.class.php
+++ b/htdocs/core/modules/modPaybox.class.php
@@ -67,9 +67,6 @@ class modPayBox extends DolibarrModules
         // Data directories to create when module is enabled.
         $this->dirs = array('/paybox/temp');
 
-        // Relative path to module style sheet if exists. Example: '/mymodule/mycss.css'.
-        $this->style_sheet = '';
-
         // Config pages. Put here list of php page names stored in admmin directory used to setup module.
         $this->config_page_url = array("paybox.php@paybox");
 
diff --git a/htdocs/core/modules/modPaypal.class.php b/htdocs/core/modules/modPaypal.class.php
index 94d2b81865e..40bcd0ca96b 100644
--- a/htdocs/core/modules/modPaypal.class.php
+++ b/htdocs/core/modules/modPaypal.class.php
@@ -68,9 +68,6 @@ class modPaypal extends DolibarrModules
         // Data directories to create when module is enabled.
         $this->dirs = array('/paypal/temp');
 
-        // Relative path to module style sheet if exists. Example: '/mymodule/mycss.css'.
-        $this->style_sheet = '';
-
         // Config pages. Put here list of php page names stored in admmin directory used to setup module.
         $this->config_page_url = array("paypal.php@paypal");