QuickBooks Integration: Error 3170

Let us talk about one of the common errors returned from QuickBooks integration when the integration process incorrectly modify the data in QuickBooks.


Status code: 3170: Status message: There was an error when modifying Vendors/Customers list, element “#######-##########”. QuickBooks error message: Cannot merge list elements.


Why does this happen? This will occur when modifying a Customer/Vendor record by referencing the record’s ListID and Customer Name, however, there is already an existing record with the same Customer Name in QuickBooks. Here is an scenario to explain this error:

We have an integration process between the QuickBooks and Salesforce where we can sync the Customer/Account from/to QuickBooks to/from Salesforce.


1. There are 2 customers in QuickBooks.

  • Customer Name #1: Tony Adam;          ListID: 1234567-1234567890
  • Customer Name #2: Ronald Williams;   ListID: 2345678-2345678901


2. These 2 records have been synced to Salesforce and they are created as Account records with the ListID as external ID.


3. User modified Customer #1 in Salesforce. The customer name is changed to Ronald Williams (same as Customer #2).


4. Customer #1 is being synced into QuickBooks via API and it tries to update the customer by the ListID. However, QuickBooks blocks this operation as it found that there is already an exsting recod found (Customer #2) with the same Customer Name but different LISTID. Hence, Customer #1 failed to be updated into QuickBooks.


Note: Customer Name must be unique in QuickBooks, this is to avoid duplication in customer records.