By default, existing files and folders are NOT deleted before restoring a backup. Therefore if the folder you want to keep exists on site B (target) but not on site A (source, the one you backed up from) you will not have any problem during the restoration.
You can exclude any file or folder from the backup. This is what the Exclude Files and Folders button in the main page of Akeeba Backup does. This feature has been around for 12 years. You'll need to do that if the folder you want to keep exists both on site B (target) and on site A (source, the one you backed up from) but you don't want its contents from site A to be restored on site B.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
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