I recently upgraded Magento from 1.5.X to 188.8.131.52.
The upgrade went smoothly and i installed a fresh new theme (https://themeforest.net/item/sawyer-multipurpose-responsive-magento-2-and-19-theme/15638656). Except for just one module in Admin - MANAGE CUSTOMERS.
This link to bring up the list of Customers, is now crawling and takes about 1 minute to load. "Customer Groups" and "Online Customers" are fine.
I really need help here and wondering if there is anyone i can turn to for help. At wits end,.
Customer module can be hidden after upgrading data.