diff --git a/htdocs/core/actions_massactions.inc.php b/htdocs/core/actions_massactions.inc.php
index 1d3d4b2adea..300c06216f7 100644
--- a/htdocs/core/actions_massactions.inc.php
+++ b/htdocs/core/actions_massactions.inc.php
@@ -377,9 +377,11 @@ if (! $error && $massaction == 'confirm_presend')
                     $subjectreplaced=make_substitutions($subject, $substitutionarray);
                     $messagereplaced=make_substitutions($message, $substitutionarray);
 
+
                     $attachedfiles=array('paths'=>array(), 'names'=>array(), 'mimes'=>array());
 					if($oneemailperrecipient)
 					{
+						// if "one email per recipient" isn't check we must collate $attachedfiles by thirdparty
 						if(is_array($attachedfilesThirdpartyObj[$thirdparty->id]) && count($attachedfilesThirdpartyObj[$thirdparty->id]))
 						{
 							foreach ($attachedfilesThirdpartyObj[$thirdparty->id] as $keyObjId =>  $objAttachedFiles){
@@ -394,6 +396,7 @@ if (! $error && $massaction == 'confirm_presend')
 					}
 					elseif(!empty($attachedfilesThirdpartyObj[$thirdparty->id][$objectid])){
 						// Create form object
+						// if "one email per recipient" isn't check we must separate $attachedfiles by object
 						$attachedfiles=$attachedfilesThirdpartyObj[$thirdparty->id][$objectid];
 					}
 
diff --git a/htdocs/core/tpl/massactions_pre.tpl.php b/htdocs/core/tpl/massactions_pre.tpl.php
index 0a273072e29..e525bd739a3 100644
--- a/htdocs/core/tpl/massactions_pre.tpl.php
+++ b/htdocs/core/tpl/massactions_pre.tpl.php
@@ -107,7 +107,8 @@ if ($massaction == 'presend')
 		$formmail->withtoreadonly = 1;
 	}
 
-	$formmail->withoptiononeemailperrecipient = (count($listofselectedref) == 1 || empty($liste))? 0 : ((GETPOST('oneemailperrecipient')=='on')?1:-1);
+	$formmail->withoptiononeemailperrecipient = ((count($listofselectedref) == 1 && count(reset($listofselectedref)) == 1) || empty($liste)) ? 0 : ((GETPOST('oneemailperrecipient')=='on')?1:-1);
+
 	$formmail->withto = empty($liste)?(GETPOST('sendto','alpha')?GETPOST('sendto','alpha'):array()):$liste;
 	$formmail->withtofree = empty($liste)?1:0;
 	$formmail->withtocc = 1;
@@ -126,6 +127,7 @@ if ($massaction == 'presend')
 
 	// Make substitution in email content
 	$substitutionarray = getCommonSubstitutionArray($langs, 0, null, $object);
+
 	$substitutionarray['__EMAIL__'] = $sendto;
 	$substitutionarray['__CHECK_READ__'] = (is_object($object) && is_object($object->thirdparty)) ? '<img src="' . DOL_MAIN_URL_ROOT . '/public/emailing/mailing-read.php?tag=' . $object->thirdparty->tag . '&securitykey=' . urlencode($conf->global->MAILING_EMAIL_UNSUBSCRIBE_KEY) . '" width="1" height="1" style="width:1px;height:1px" border="0"/>' : '';
 	$substitutionarray['__PERSONALIZED__'] = '';	// deprecated