diff --git a/scripts/Diffraction/isis_powder/routines/run_details.py b/scripts/Diffraction/isis_powder/routines/run_details.py
index 6891f89311f6c732e3ca709135ca0777845162ca..c8cdd7c99e844cb6e91c23643d7df692e24a713d 100644
--- a/scripts/Diffraction/isis_powder/routines/run_details.py
+++ b/scripts/Diffraction/isis_powder/routines/run_details.py
@@ -60,7 +60,7 @@ def create_run_details_object(run_number_string, inst_settings, is_vanadium_run,
         file_extension = file_extension if file_extension.startswith('.') else '.' + file_extension
 
     # Get the output name suffix if set
-    suffix = getattr(inst_settings, "suffix")
+    suffix = getattr(inst_settings, "suffix", None)
 
     # Sample empty if there is one as this is instrument specific
     sample_empty = getattr(inst_settings, "sample_empty", None)