...

src/calibre/constants.py

@@ -45,6 +45,7 @@ fcntl      = None if iswindows else importlib.import_module('fcntl')
 filesystem_encoding = sys.getfilesystemencoding()
 if filesystem_encoding is None: filesystem_encoding = 'utf-8'
 
+
 DEBUG = False
 
 def debug():

src/calibre/startup.py

@@ -61,6 +61,12 @@ if not _run_once:
 
     ################################################################################
     # Initialize locale
+    # Import string as we do not want locale specific
+    # string.whitespace/printable, on windows especially, this causes problems
+    # Before the delay load optimizations, string was loaded before this point
+    # anyway, so we preserve the old behavior, explicitly.
+    import string
+    string
     try:
         locale.setlocale(locale.LC_ALL, '')
     except: