Tax settings from the Sales menu have disappeared. It appears this is a conflict with a certain module, when I disable this module from
app/etc/modules the tax menu reappears.
No menu items from the module are visible.
However, I have not been able to find out the root cause for the problem. All module XML-files seem to be in order. This module and taxes were working before and no changes to the XML-files have been made.
Also I have a local test env, where the module is working. Code is an exact copy in both locations.
I have checked the Magento roles and permissions, everything OK there.
What could possibly cause this behaviour? Could it be some configuration or other setting. If so, what?