diff --git a/wcs/qommon/storage.py b/wcs/qommon/storage.py
index dc2e6a4af..5670f5361 100644
--- a/wcs/qommon/storage.py
+++ b/wcs/qommon/storage.py
@@ -25,6 +25,7 @@ import sys
 import tempfile
 
 from django.utils import six
+from django.utils.encoding import force_bytes
 from django.utils.six.moves import _thread
 
 from .vendor import locket
@@ -310,7 +311,7 @@ class StorableObject(object):
     @classmethod
     def has_key(cls, id):
         filename = os.path.join(cls.get_objects_dir(), fix_key(id))
-        return os.path.exists(filename)
+        return os.path.exists(force_bytes(filename, 'utf-8'))
 
     @classmethod
     def get_new_id(cls, create=False):
@@ -400,7 +401,7 @@ class StorableObject(object):
     @classmethod
     def get_filename(cls, filename, ignore_errors=False, ignore_migration=False, **kwargs):
         try:
-            fd = open(filename, 'rb')
+            fd = open(force_bytes(filename, 'utf-8'), 'rb')
             o = cls.storage_load(fd, **kwargs)
         except IOError:
             if ignore_errors: