AttributeError when adding sharing permission to a user - error-handling

Question

When I assign a new sharing permission level to any user,
I get this error
It seems that any folder or user produces this error. There are some users with sharing permissions already, which means this used to work before. I'm not sure what happened from then until now that changed this.
Have any of you encountered this problem before?
Error log :
Traceback (innermost last):
Module ZPublisher.Publish, line 115, in publish
Module ZPublisher.mapply, line 88, in mapply
Module ZPublisher.Publish, line 41, in call_object
Module Products.CMFCore.FSPythonScript, line 108, in __call__
Module Shared.DC.Scripts.Bindings, line 311, in __call__
Module Shared.DC.Scripts.Bindings, line 348, in _bindAndExec
Module Products.CMFCore.FSPythonScript, line 164, in _exec
Module None, line 14, in folder_localrole_edit
- <FSPythonScript at /intranet/folder_localrole_edit used for /intranet/service-areas/management-services>
- Line 14
Module <string>, line 4, in _facade
Module Products.Hotfix_20070320, line 68, in _curried
Module Products.CMFCore.MembershipTool, line 437, in setLocalRoles
Module Products.Archetypes.CatalogMultiplex, line 70, in reindexObjectSecurity
Module Products.ZCatalog.CatalogBrains, line 52, in _unrestrictedGetObject
Module OFS.Traversable, line 187, in unrestrictedTraverse
- __traceback_info__: (['mailer', 'formfolder.2009-03-22.3253705634', 'FormFolder', 'portal_factory'], 'one-melville-brand-update-2009-1')
Module Products.Five.traversable, line 126, in __bobo_traverse__
AttributeError: one-melville-brand-update-2009-1

Answer 1

It seems like your portal_catalog tool is inconsistent.
This means you have catalog entries (brain), with no real content (Archetype object).
You can solve this by "Clear and Rebuild" your catalog.
http://localhost:8080/${PATH_TO_PLONE}/portal_catalog/manage_catalogAdvanced -> Clear and rebuilt.
This action can take long time, depending on how many content you have.
Short explanation what seems to happen in your case:
After changing the local roles on a specific object, Plone tries to reindex the security relevant portal catalog indexes on the object itself and on all subobjects. While reindexing the subcontent it tries to get some data of a inexistent object (AttributeError while traversal).
With a fresh catalog you can avoid such errors.