How to set an error message on a custom field (of person record) if webhook failed?
Similar article: Adding Webhook Error log to email alert
As I answered on the other thread, there's no token for a failed response. You can capture the fact that there was an error (and filter by error codes) using Webhook Was Called.
Ifyou have a remote service that uses HTTP errors + data payloads to send responses (this isn't a good practice for any web service) then you have to put another service between Marketo and that service to translate appropriately.
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