Error: Unknown duplicates value on record with id

Question

I'm trying to Upsert the data to Account object using an external tool, Everything works fine but Salesforce is throwing error for few records when upserting.

I was doing the upsertion process using the external id field. Except external id field no other field is having a unique constraint.

I'm getting the following error -

SF_ERROR: DUPLICATE_VALUE

OBJ: Account - duplicate value found: unknown duplicates value on record with id: 001***********

Please help me to solve the issue.

Answer 1

This is happening because your trying to create Salesforce contact multiple times with same email and data

Answer 2

It's silly but this was happening to me because SFDC considers 'NULL' as a unique value... Mostly because Excel converted 'NULL' to text and was trying to bring in the literal word 'NULL'.