Understanding the Root Cause

The root cause of this issue is the inconsistent use of subscriber keys between SFMC and Sales Cloud. When PersonAccounts are enabled, Sales Cloud uses the PersonContactID as the primary identifier, while SFMC may still be using the AccountID. This mismatch leads to the creation of duplicate records in the All Subscribers list.

To illustrate this issue, consider a scenario where a customer has an AccountID of 12345 and a PersonContactID of 67890. If SFMC sends an email using the AccountID as the subscriber key, and then Sales Cloud sends an email using the PersonContactID, two separate records will be created in the All Subscribers list, one for each identifier.

Resolving the Issue

To resolve this issue, teams can either standardize on using PersonContactID as the subscriber key across both SFMC and Sales Cloud or migrate existing AccountID subscribers to PersonContactID. The first option requires updating the subscriber key in SFMC to use PersonContactID and then performing a mass delete of all subscribers identified by AccountID. The second option involves paying Salesforce to migrate the existing AccountID subscribers to PersonContactID.

Additionally, teams should review their data extensions (DEs) to ensure that the lookup fields are correctly configured to use PersonContactID instead of AccountID. This includes updating the Account child object DEs to use the correct lookup field.

Implementation Steps

SFMC Configuration

UPDATE SubscriberKey SET SubscriberKey = PersonContactID WHERE SubscriberKey = AccountID

Once the subscriber key is standardized, teams can perform a mass delete of all subscribers identified by AccountID to remove duplicates from the All Subscribers list.

Best Practices and Next Steps

Checklist for Resolving Duplicate Subscribers

• Standardize the subscriber key used across SFMC and Sales Cloud
• Update the subscriber key in SFMC to use PersonContactID
• Perform a mass delete of all subscribers identified by AccountID
• Review and update DEs to use the correct lookup field
• Test and verify the changes to ensure duplicates are removed
• Monitor the All Subscribers list for any future duplicates

By following these steps and best practices, teams can resolve the issue of duplicate subscribers and ensure a consistent and accurate All Subscribers list in SFMC.

Frequently Asked Questions

What is the impact of using different subscriber keys in SFMC and Sales Cloud?

Using different subscriber keys can lead to duplicate records in the All Subscribers list, causing confusion and potential issues with email sends.

How do I update the subscriber key in SFMC to use PersonContactID?

Update the subscriber key in SFMC by running a query to set the SubscriberKey to PersonContactID where the SubscriberKey is currently set to AccountID.

What is the cost of migrating existing AccountID subscribers to PersonContactID?

The cost of migrating existing AccountID subscribers to PersonContactID varies and should be discussed with Salesforce directly.

How do I prevent duplicate subscribers in the future?

To prevent duplicate subscribers, ensure that the subscriber key is standardized across SFMC and Sales Cloud, and regularly monitor the All Subscribers list for any duplicates.