Any "Role Resources" I assign are reverted back to "none", having the effect that none of the API Users have any privileges.
Please advice the solution. Thank you.
Workaround:
Run this MySQL query:
delete from `api_rule` where api_permission='deny'
This will remove all 'deny' API rules and is probably insecure hack but it's probably better than having no Magento Web Service API access at all.
( Referenced thread on Magento Commerce Forums )
