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Navigate to Admin > User Management > Permissions Sets.
Click the button.
Enter a 'Name' of "CustomerCenter Only".
This title lets other Users easily know the intent of the Permissions Set.
Leave the 'Default Permission for Menus & Modules/Controllers:' set to 'Deny'. This ensures access to ONLY what is added.
On the 'Menu' tab, click the 'Add' button.
This opens the 'Add New Menu Permissions' form. Click the 'CustomerCenter Menu' field.
Select 'Check all'.
Click the button.
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