how to enable Magento Customer Account Sharing to global?

Question

I am getting the following problem while turning on:

System>Configuration>Default>Customer Configuration>Share Customer Accounts to Global

"Cannot share customer accounts globally because some customer accounts with the same emails exist on multiple websites and cannot be merged"

Why is this problem showing?

Any solution?

Answer 1

You will need to delete all the duplicate email address leaving only 1 record

To find all duplicate emails

SELECT * FROM customer_entity group by email having count(email) > 1;

You can start by deleting all the duplicating customers email that don't have an order associated with it (by joining the order tables).

If a customer made purchase from multiple stores then you will still need to delete one of the customer_entity but you could always update the customer_id in the order table to match the new customer id