I created a custom object so that I could push leads from an external API and have Marketo look at another field then the email address as the dedup field. It worked and I was able to create a new lead even though they had the same email address, but when I tried to sync the 2nd, 3rd, 4th, etc, lead to Salesforce the sync failed. This is the error I received, "Failed: the record is filtered in sfdc - 00QP0000003X0lcMAC”.
Has anyone ever come across this error before or know what it mean?
The way your sync is set up is filtering some records in SFDC to NOT synch with Marketo. Once the filter is set, it prevents some records that you do not want to sync from sync'ing.
In this case, your leads used to sync, which is why they exist on both systems, then some value change activated the filter for them and you can no longer sync them.