[python-win32] Problem with Check: can't decode byte 0x90

[bob gailer]

My program loads into an edit window and runs fine.

Top line :  # -*- coding: utf-8 -*-

However when I invoke check (shift-ctl-c) I get:
Traceback (most recent call last):
   File 
"C:\Python33\Lib\site-packages\pythonwin\pywin\framework\intpyapp.py", 
line 335, in OnFileCheck
     scriptutils.CheckFile()
   File 
"C:\Python33\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py", line 
467, in CheckFile
     code = f.read() + "\n"
   File "C:\Python33\lib\encodings\cp1252.py", line 23, in decode
     return codecs.charmap_decode(input,self.errors,decoding_table)[0]
UnicodeDecodeError: 'charmap' codec can't decode byte 0x90 in position 
19689: character maps to <undefined>

How do we fix this?