On this page, you will find more information about the most common causes and most relevant solutions for the Emarsys error '3003 - Invalid datatype for the list of external IDs. Array expected'. Do you need help straight away? Visit our support page.
The emarsys eMarketing Systems documentation indicates that error code '3003 - Invalid datatype for the list of external IDs. Array expected' is caused by the following problem: "Specify an array.".
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