diff --git a/trove/guestagent/common/operating_system.py b/trove/guestagent/common/operating_system.py
index f4aacdbad1..d52229e8e8 100644
--- a/trove/guestagent/common/operating_system.py
+++ b/trove/guestagent/common/operating_system.py
@@ -248,6 +248,7 @@ def file_discovery(file_candidates):
     for file in file_candidates:
         if os.path.isfile(file):
             return file
+    return ''
 
 
 def start_service(service_candidates):
diff --git a/trove/tests/unittests/guestagent/test_operating_system.py b/trove/tests/unittests/guestagent/test_operating_system.py
index c38b98e470..d43cd2fbed 100644
--- a/trove/tests/unittests/guestagent/test_operating_system.py
+++ b/trove/tests/unittests/guestagent/test_operating_system.py
@@ -819,6 +819,10 @@ class TestOperatingSystem(trove_testtools.TestCase):
             config_file = operating_system.file_discovery(
                 ["/etc/mongodb.conf", "/etc/mongod.conf"])
         self.assertEqual('/etc/mongod.conf', config_file)
+        with patch.object(os.path, 'isfile', side_effect=[False]):
+            config_file = operating_system.file_discovery(
+                ["/etc/mongodb.conf"])
+        self.assertEqual('', config_file)
 
     def test_list_files_in_directory(self):
         root_path = tempfile.mkdtemp()