Hi Hoi,It's not really Marketo detecting a duplicate. The message being returned is originating from Salesforce when it rejects the attempt to insert a new record. It's possible yo...
It's not possible to answer that without seeing how form fill is being recorded for the lead that filled out the form, and without seeing how exactly you set up your Smart Campaign...
It sounds like you're attempting a Sync Lead to SFDC action on an unsynced Marketo record and hoping that it links up to an existing record in Salesforce with the same email addres...
Nope. The Program/Campaign association is always set in Marketo. You can create a new SFDC Campaign from Marketo but you cannot create a new Marketo program from SFDC.