diff --git a/sale_order_invoicing_finished_task/i18n/sk.po b/sale_order_invoicing_finished_task/i18n/sk.po
new file mode 100644
index 000000000000..1c56da12b103
--- /dev/null
+++ b/sale_order_invoicing_finished_task/i18n/sk.po
@@ -0,0 +1,89 @@
+# Translation of Odoo Server.
+# This file contains the translation of the following modules:
+# * sale_order_invoicing_finished_task
+# 
+# Translators:
+# OCA Transbot <transbot@odoo-community.org>, 2018
+msgid ""
+msgstr ""
+"Project-Id-Version: Odoo Server 10.0\n"
+"Report-Msgid-Bugs-To: \n"
+"POT-Creation-Date: 2018-01-27 03:53+0000\n"
+"PO-Revision-Date: 2018-01-27 03:53+0000\n"
+"Last-Translator: OCA Transbot <transbot@odoo-community.org>, 2018\n"
+"Language-Team: Slovak (https://www.transifex.com/oca/teams/23907/sk/)\n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=UTF-8\n"
+"Content-Transfer-Encoding: \n"
+"Language: sk\n"
+"Plural-Forms: nplurals=3; plural=(n==1) ? 0 : (n>=2 && n<=4) ? 1 : 2;\n"
+
+#. module: sale_order_invoicing_finished_task
+#: model:ir.model.fields,help:sale_order_invoicing_finished_task.field_product_product_invoicing_finished_task
+#: model:ir.model.fields,help:sale_order_invoicing_finished_task.field_product_template_invoicing_finished_task
+#: model:ir.model.fields,help:sale_order_invoicing_finished_task.field_project_task_invoicing_finished_task
+msgid "Invoice the order lines only when the task is in folded stage"
+msgstr ""
+
+#. module: sale_order_invoicing_finished_task
+#: model:ir.model.fields,field_description:sale_order_invoicing_finished_task.field_project_task_invoiceable
+#: model:ir.model.fields,field_description:sale_order_invoicing_finished_task.field_project_task_type_invoiceable
+msgid "Invoiceable"
+msgstr ""
+
+#. module: sale_order_invoicing_finished_task
+#: model:ir.model.fields,field_description:sale_order_invoicing_finished_task.field_product_product_invoicing_finished_task
+#: model:ir.model.fields,field_description:sale_order_invoicing_finished_task.field_product_template_invoicing_finished_task
+#: model:ir.model.fields,field_description:sale_order_invoicing_finished_task.field_project_task_invoicing_finished_task
+msgid "Invoicing finished task"
+msgstr ""
+
+#. module: sale_order_invoicing_finished_task
+#: model:ir.model,name:sale_order_invoicing_finished_task.model_product_template
+msgid "Product Template"
+msgstr ""
+
+#. module: sale_order_invoicing_finished_task
+#: model:ir.model,name:sale_order_invoicing_finished_task.model_sale_order
+msgid "Sales Order"
+msgstr "Objednávka predaja"
+
+#. module: sale_order_invoicing_finished_task
+#: model:ir.model,name:sale_order_invoicing_finished_task.model_sale_order_line
+msgid "Sales Order Line"
+msgstr ""
+
+#. module: sale_order_invoicing_finished_task
+#: model:ir.model,name:sale_order_invoicing_finished_task.model_project_task
+msgid "Task"
+msgstr ""
+
+#. module: sale_order_invoicing_finished_task
+#: model:ir.model,name:sale_order_invoicing_finished_task.model_project_task_type
+msgid "Task Stage"
+msgstr ""
+
+#. module: sale_order_invoicing_finished_task
+#: model:ir.model.fields,field_description:sale_order_invoicing_finished_task.field_sale_order_line_task_ids
+msgid "Tasks"
+msgstr ""
+
+#. module: sale_order_invoicing_finished_task
+#: code:addons/sale_order_invoicing_finished_task/models/project.py:70
+#, python-format
+msgid "You cannot add a task to and invoiced Sale Order Line"
+msgstr ""
+
+#. module: sale_order_invoicing_finished_task
+#: code:addons/sale_order_invoicing_finished_task/models/project.py:55
+#, python-format
+msgid "You cannot modify the Sale Order Line of the task once it is invoiced"
+msgstr ""
+
+#. module: sale_order_invoicing_finished_task
+#: code:addons/sale_order_invoicing_finished_task/models/project.py:45
+#, python-format
+msgid ""
+"You cannot modify the status if there is no Sale Order Line or if it has "
+"been invoiced."
+msgstr ""
diff --git a/sale_order_invoicing_finished_task/models/project.py b/sale_order_invoicing_finished_task/models/project.py
index 74d5dc8d69b4..6b59cecadf58 100644
--- a/sale_order_invoicing_finished_task/models/project.py
+++ b/sale_order_invoicing_finished_task/models/project.py
@@ -70,7 +70,7 @@ def create(self, vals):
             raise ValidationError(_('You cannot add a task to and invoiced '
                                     'Sale Order Line'))
         # Onchange stage_id field is not triggered with statusbar widget
-        if 'sale_line_id' in vals:
+        if 'sale_line_id' in vals and 'stage_id' in vals:
             stage = self.env['project.task.type'].browse(vals['stage_id'])
             if so_line.product_id.invoicing_finished_task and \
                     stage.invoiceable: