Hi Ham,
Most likely you have a db that was installed an ecommerce module
already. So the problem maybe the drop scripts not cleaning out
properly. You should be able to look at the sql see what is the
value that causing the duplicate and manually nuke it in the
meantime.
If you are doing this in the office maybe I can help tomorrow. If
you are in the house then good luck I know you can figure this out
without any difficulty.
