I've had an issue come up several times in the past couple days, so I thought I would blog it out for use in the future.
So, you have Salesforce with some records that are not synced to Marketo. Over on the Marketo side, one of those SFDC-record people fills out a Marketo form and enters the Marketo database. Now you have two records for the same person, and they aren't synced. Marketo will try to push the not-actually-new record to Salesforce, but if you have duplicate suppression in Salesforce, SFDC will reject it. So what do you do?
Because I'm inclined to silliness, I'm going to personify these records as Mr. Salesforce and Ms. Marketo, star-crossed lovers who we need to unite. How do we bring them together? Since Salesforce is clearly not having this duplicate situation, we have to get both members of the couple into Marketo, who is much less fussy about such things. To do this, we need to make Mr. Salesforce's record visible to the Marketo Sync User, so that he can sync over to Marketo.
Once Mr. Salesforce arrives in Marketo on the sync, we can marry him to Ms. Marketo using the Merge function in Marketo. Once the records are merged, we have the happy couple, Mr. and Mrs. Salesforce-Marketo, who are able to communicate with each other across the sync.
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