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To map other custom fields, please refer to the instructions here: 7.3.4.1 Map and transfer data into DFP custom fields

Map the Campaign Items Alternate ID

By selecting a value for the Campaign Item field Alternate ID this value will be transferred to the field External ID in the GAM (DFP) Line Item.

If no value is set, the Salesforce record ID of your Campaign Item will be transferred into the field.

Map the Account's External ID

To map the advertiser ID choose which field you like to transfer in the DFP Adserver login:

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This will lead to filling out the following field in DFP

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