When disabling url aliasing in the system, when you go back to re-activate it you must activate all url aliases again before they will become active. Re-enabling aliasing itself will not activate the aliases.
- When in the workarea navigate to Settings > Configuration > Url Aliasing > Settings
- Enable the alias types you want to display on the website
- Navigate to Aliases and you will notice they are not marked as active.
- Check edit and check off the active column
- Click Save and try your aliases again.