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- Copy all of your files from your server to your local computer using an FTP client
This method is only possible if your hosting provider has provided you with an FTP access to your server. Create a "Backup" folder on your computer, then, using an FTP client (such as the free FileZilla client, which you can download at http://filezilla-project.org/), select all the PrestaShop files and folders on your server (use the Ctrl-A command) and copy them to your "Backup" folder.
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In the "Maintenance IP" field, located just below the "Enable Shop" one, enter your own IP address, so that you can keep on using your store during the update. This will allow you to test the store, while still making sure visitors cannot access the website.
In order to find out your IP address, visit this page: http://wwwwhatismyipaddress.myip.dkcom/
Backing Up Your Database
You must absolutely back up the whole database for your PrestaShop store.
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