Getting a 'Not Permitted' Error After Upgrading from Confluence 2.6.x Or Below
When upgrading Confluence 2.6.x or below to a later version eg. 3.1.x or later, Confluence reports a 'Not Permitted' error when trying to login.
LDAP Group membership unfortunately is not retained when using OSUser management and LDAP. This is a known problem that has been filed in CONF-10654.