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Customers can register to your shop's newsletter directly using this form. Afterwards, the newsletter itself is entirely managed by you; PrestaShop does not handle the transmission of e-mails to the customers.
The "Newsetter" module enables you to generate a .CSV file of all the the registered customers and their e-mails, and you should be able to import that CSV file in any e-mailing system.
The right column
The default theme's right column hardly ever changes in the course of the shopping experience.
These blocks are always available, from any page, in the default theme.
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