diff --git a/product/ERP5Type/tests/ERP5TypeLiveTestCase.py b/product/ERP5Type/tests/ERP5TypeLiveTestCase.py
index 26bc3d8f2fe7fcdc54fdbe8edaa3679568bf9956..4bbc480912b04e5078fedc73eea564a7a5c31ae3 100644
--- a/product/ERP5Type/tests/ERP5TypeLiveTestCase.py
+++ b/product/ERP5Type/tests/ERP5TypeLiveTestCase.py
@@ -143,6 +143,12 @@ class ERP5TypeLiveTestCase(ERP5TypeTestCaseMixin):
     def _setup(self):
         '''Change some site properties in order to be ready for live test
         '''
+        # force a random password for ERP5TypeTestCase user by removing
+        # any existing one
+        try:
+          self.portal.acl_users.zodb_users.removeUser('ERP5TypeTestCase')
+        except (AttributeError, KeyError):
+          pass
         # Disabling portal_activities is required in order to avoid
         # conflict with other threads doing tic in the same time
         self.login()