Schönen guten Abend!

I have a nice script that should complete a certain kind of blocking which is usual: blocks the user, puts a template on the user page, redirects the talk page to the user page and protects both pages.

This script ran previously without an error, but yesterday it failed, tough I was so happy to use it instead of doing manually the whole process. The message is:
C:\Program Files\Pywikipedia>p baz.py
Traceback (most recent call last):
  File "baz.py", line 190, in <module>
    main()
  File "baz.py", line 184, in main
    bot.run()
  File "baz.py", line 82, in run
    if user.block(expiry='infinite', reason=blockmessage):
  File "C:\Program Files\Pywikipedia\userlib.py", line 384, in block
    raise UserActionRefuse('You don\'t have permission to block')
userlib.UserActionRefuse: You don't have permission to block

I have the almost latest pywiki, but the bot was tested with an end-July version (8362). Since then two things have changed:
*I updated pywiki to 8656 this weekend.
*I installed Python 3.1.2 as default, and I run my pywiki scripts with p something.py, as described in thread "Two Pythons on one Windows". I suppose, once I started a script under Python, the imported modules don't need to specify the path of Python to use.
User-config.py is the same except that I added new lines for a Wikia-wiki.

Which of these could cause my problem?

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Bináris