[Zope] Error accessing top "Security" tab

[R. Herold]

Dear Zope users,

when I try to access the Zope top/root "Security" tab but (and only with
this Security tab), the following error occurs:

Traceback (innermost last):
  File /opt/zope/lib/python/ZPublisher/Publish.py, line 214, in
publish_module
  File /opt/zope/lib/python/ZPublisher/Publish.py, line 179, in publish
  File /opt/zope/lib/python/Zope/__init__.py, line 202, in
zpublisher_exception_hook
    (Object: ApplicationDefaultPermissions)
  File /opt/zope/lib/python/ZPublisher/Publish.py, line 165, in publish
  File /opt/zope/lib/python/ZPublisher/mapply.py, line 160, in mapply
    (Object: manage_access)
  File /opt/zope/lib/python/ZPublisher/Publish.py, line 102, in call_object
    (Object: manage_access)
  File /opt/zope/lib/python/AccessControl/Role.py, line 231, in
manage_access
    (Object: ApplicationDefaultPermissions)
  File /opt/zope/lib/python/App/special_dtml.py, line 120, in __call__
    (Object: access)
    (Info: /opt/zope/lib/python/AccessControl/access.dtml)
  File /opt/zope/lib/python/DocumentTemplate/DT_String.py, line 502, in
__call__
    (Object: access)
  File /opt/zope/lib/python/DocumentTemplate/DT_With.py, line 148, in render
    (Object: _.namespace(valid_roles=valid_roles()))
  File /opt/zope/lib/python/DocumentTemplate/DT_In.py, line 630, in
renderwob
    (Object: permission_settings)
  File /opt/zope/lib/python/AccessControl/Role.py, line 166, in
permission_settings
    (Object: ApplicationDefaultPermissions)
  File /opt/zope/lib/python/AccessControl/Role.py, line 161, in <lambda>
TypeError: (see above)

-------

So far, I used Zope luckily, especially the Portal, but these days I tried
to work some more on it and maybe added a product or tried to alter some
security options, but I can't attribute the occurrence of this error to one
specific thing I did.

Could You help, please, how to find out what to do and how to
re-establish this folder? THANKS! Greetings from Berlin,

  Ralf Herold

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