diff --git a/addons/mail/static/src/js/models/mail_failure.js b/addons/mail/static/src/js/models/mail_failure.js
index 390b195f8d9..9a007954a5a 100644
--- a/addons/mail/static/src/js/models/mail_failure.js
+++ b/addons/mail/static/src/js/models/mail_failure.js
@@ -13,6 +13,7 @@ var MailFailure = Class.extend(Mixins.EventDispatcherMixin, ServicesMixin, {
     /**
      * @param {mail.Manager} parent
      * @param {Object} data
+     * @param {string} data.failure_type
      * @param {string} data.last_message_date
      * @param {integer} data.message_id
      * @param {string} data.model
@@ -29,6 +30,7 @@ var MailFailure = Class.extend(Mixins.EventDispatcherMixin, ServicesMixin, {
 
         this._documentID = data.res_id;
         this._documentModel = data.model;
+        this._failureType = data.failure_type || 'mail';
         this._lastMessageDate = moment(); // by default: current datetime
         this._messageID = data.message_id;
         this._modelName = data.model_name;
@@ -62,6 +64,14 @@ var MailFailure = Class.extend(Mixins.EventDispatcherMixin, ServicesMixin, {
     getDocumentID: function () {
         return this._documentID;
     },
+    /**
+     * Get the type of failure of this mail failure.
+     *
+     * @returns {string}
+     */
+    getFailureType: function () {
+        return this._failureType;
+    },
     /**
      * Get the ID of the message that this mail failure is related to.
      *
diff --git a/addons/mail/static/src/js/services/mail_manager.js b/addons/mail/static/src/js/services/mail_manager.js
index 6a49cdf0183..062b3208066 100644
--- a/addons/mail/static/src/js/services/mail_manager.js
+++ b/addons/mail/static/src/js/services/mail_manager.js
@@ -676,8 +676,8 @@ var MailManager =  AbstractService.extend({
     },
     /**
      * Get the previews of the mail failures
-     * Mail failures of a same model are grouped together, so that there are few
-     * preview items on the messaging menu in the systray.
+     * Mail failures of a same model with the same type are grouped together, so
+     * that there are few preview items on the messaging menu in the systray.
      *
      * To determine whether this is a model preview or a document preview review
      * the documentID is omitted for a model preview, whereas it is set for a
@@ -696,10 +696,11 @@ var MailManager =  AbstractService.extend({
         _.each(this._mailFailures, function (failure) {
             var unreadCounter = 1;
             var isSameDocument = true;
-            var sameModelItem = _.find(items, function (item) {
+            var sameModelAndTypeItem = _.find(items, function (item) {
                 if (
                     item.failure.isLinkedToDocument() &&
-                    (item.failure.getDocumentModel() === failure.getDocumentModel())
+                    (item.failure.getDocumentModel() === failure.getDocumentModel()) &&
+                    (item.failure.getFailureType() === failure.getFailureType())
                 ) {
                     isSameDocument = item.failure.getDocumentID() === failure.getDocumentID();
                     return true;
@@ -707,10 +708,10 @@ var MailManager =  AbstractService.extend({
                 return false;
             });
 
-            if (failure.isLinkedToDocument() && sameModelItem) {
-                unreadCounter = sameModelItem.unreadCounter + 1;
-                isSameDocument = sameModelItem.isSameDocument && isSameDocument;
-                var index = _.findIndex(items, sameModelItem);
+            if (failure.isLinkedToDocument() && sameModelAndTypeItem) {
+                unreadCounter = sameModelAndTypeItem.unreadCounter + 1;
+                isSameDocument = sameModelAndTypeItem.isSameDocument && isSameDocument;
+                var index = _.findIndex(items, sameModelAndTypeItem);
                 items[index] = {
                     unreadCounter: unreadCounter,
                     failure: failure,