diff --git a/wcs/wf/export_to_model.py b/wcs/wf/export_to_model.py
index c7a034cf3..9585863e2 100644
--- a/wcs/wf/export_to_model.py
+++ b/wcs/wf/export_to_model.py
@@ -75,7 +75,7 @@ try:
                                       stderr=dev_null)
             return open(infile.name + '.pdf')
         except subprocess.CalledProcessError:
-            return False
+            raise Exception('libreoffice is failing')
         finally:
             shutil.rmtree(temp_dir)
 except subprocess.CalledProcessError: