[Setup] Cannot Add File after migration 2.0.5 to 2.1.3

[René Pijlman]

Peter Arathoon wrote:
> I have tried resetting all permissions through root-level and Plone instance level Security Tab, and even at the folder level, (Modify Portal Content, Add File, Add ATCT FIle, ...) and also through the workflow settings for folder-workflow and plone-workflow, but with no luck.
The procedure to debug permission problems is to replay the scenario 
that triggers the "Insufficient privileges" error with VerboseSecurity 
enabled:
http://plone.org/documentation/how-to/debug-unauthorized