urlopen issues for http POST in Windows.

[foco]

I have a simple script to POST a pdf to a server. It works great when I use Ubuntu to run it. However, when I run it in Windows, I get this error:

Error: <urlopen error [Errno 10035] A non-blocking socket operation could not be completed immeditately>

Could this be a problem specific to the code, or with firewalls, etc?
Do you recommend any ways to fix this?

import urllib, urllib2, time, os

#Reads pdf data
pdf = open("testpdf.pdf", "rb").read() 

url = 'http://apx.enotz.com' #the server to post to

values = {'c' : 'print', #the command
          'psid' : 'DE5', #the venue
          'pcn' : '0105050505', #print card number
          'theFile' : 'testpdf.pdf', #file name of pdf
          'theData' : pdf, #the data
          }

try:
    data = urllib.urlencode(values) #properly encodes parameters 
    req = urllib2.Request(url, data)
    response = urllib2.urlopen(req)
    the_page = response.read() 
    print the_page 
except Exception, detail: #if non-standard error occured 
    print "Error: ", detail