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You must enable "Warehousing" as one of the Supplier's activities.
To do it go to Suppliers → Suppliers → View Suppliers → Suppliers → Capabilities tab tab.
Users tab
- Create a Supplier User for the warehouse Supplier to use when calling the web services. For this, follow the instructions for Adding a Supplier User
- Name the Supplier User "Web Services".
- Enter the email address into the 'Email' and ‘External ID’ fields.
- Create a password that the warehouse system can use and inform the warehouse supplier of the email address and password so they can configure their system.
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