Logged In: YES 
user_id=1276121

for the subprocess.py I did the following in a few places

try:
    _active.remove(self)
except:
    pass

see also bug 1199282
https://sourceforge.net/tracker/index.php?func=detail&aid=1199282&group_id=5470&atid=105470

in my current script I circumvent the "Permission denied"
error in the following way:

removed = False
while not removed:
try:
    os.remove(file)
    except OSError, error:
        logger.warning("could not remove file %s, %s"
%(file, error))
        time.sleep(1)
    else:
        removed = True

I also have a virus scanner (Mcafee, corporate stuff), and
still get the same behaviour when disabling the virus scanner.

>My feel, after staring at filemon output, is that this is a
>problem in the Windows file I/O layer.  NTFS queues the
>various operations, and calling an external process with
>stuff still in the queue messes up the request scheduling.

this seems strange to me, since every thread works with its
own temp files, and all requests are send one after another
to the file I/O layer