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You can create as many profiles as needed, by using the "Profiles" page in the "Administration" menu, and then clicking on "Add new". Type de the profile's name, validate it, then go edit its permission in the "Permissions" page.
By default, a new profile cannot do much. It is up to you to set exactly the parts of your shop to which that profile should have access. It can be a tedious task, but it is an important one.
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