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Some users do not automatically have access to the named credential that was created, as it is not included in the Filenize User or Admin permission set. To resolve this, you need to clone the Filenize User or Admin create a new permission set or edit the user’s profile, edit it, :
Legacy: open Named Credential Access, and add your named credential to the Enabled Named Credentials column.
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New Named Credentials: open External Credential Principle Access, and add your principle to the Enabled External Credential Principals column.
Users don’t see Authentication Settings for External Users under their personal settings
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