I have a very old store that has been through hell, it's basically held together with duct tape. It started life as magento 1.7 then went through upgrades, dozens of extensions installed and uninstalled, custom templates that add "tools" to the magento backend. I made a copy on a development server and tried to upgrade it to 2.2 or 2.3 version of magento with no luck.
Now I'm trying something new. I installed a brand new version of Magento 2.3.3 on the development server, and I'd like to bring in my customer data, my orders, and my products into it. I'm going to be making a new theme, and I'm fine with reconfiguring everything from scratch. I'd just like to keep the close to 10 years of customer info and products.
You can check this migration tool for migrating data from Magento 2.1.15 to 2.3.3
This tool allows you to automatically transfer data including: products, customers, orders, categories, manufacturers, taxes, coupons, reviews, multistore, cms pages, multiple languages from Magento 2.2 to Magento 2.3.
But first check its demo before using it and if it works as per your expectations then go with it.
Thanks
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