diff --git a/django/db/__init__.py b/django/db/__init__.py
index 58d66b02c8..d15fd3238e 100644
--- a/django/db/__init__.py
+++ b/django/db/__init__.py
@@ -24,7 +24,10 @@ except ImportError, e:
         # The database backend wasn't found. Display a helpful error message
         # listing all possible (built-in) database backends.
         backend_dir = os.path.join(__path__[0], 'backends')
-        available_backends = [f for f in os.listdir(backend_dir) if not f.startswith('_') and not f.startswith('.') and not f.endswith('.py') and not f.endswith('.pyc')]
+        try:
+            available_backends = [f for f in os.listdir(backend_dir) if not f.startswith('_') and not f.startswith('.') and not f.endswith('.py') and not f.endswith('.pyc')]
+        except EnvironmentError:
+            available_backends = []
         available_backends.sort()
         if settings.DATABASE_ENGINE not in available_backends:
             raise ImproperlyConfigured, "%r isn't an available database backend. Available options are: %s\nError was: %s" % \