diff -up hplip-3.14.6/base/utils.py.codec hplip-3.14.6/base/utils.py
--- hplip-3.14.6/base/utils.py.codec	2014-07-09 10:35:11.813576899 +0100
+++ hplip-3.14.6/base/utils.py	2014-07-09 10:43:20.786495160 +0100
@@ -463,7 +463,12 @@ def sort_dict_by_value(d):
 
 
 def commafy(val):
-    return locale.format("%d", val, grouping=True).decode(locale.getpreferredencoding())
+    format = locale.format("%d", val, grouping=True)
+    encoding = locale.getlocale(locale.LC_NUMERIC)[1]
+    if encoding == None:
+        return format
+
+    return format.decode(encoding)
 
 
 def format_bytes(s, show_bytes=False):