Error: This key value already exists. Duplicates are not allowed. is received when trying to create a partitioned supplier profile from the User Interface (UI).

The previously existing supplier profile is inactive and still produces the error. Earlier entries for the same supplier profile existed with the same UniqueName. That profile was deleted from the system, instead of deactivating it. This inactive supplier profile, which was deleted from the system, caused this issue.

To resolve this issue, you must reimport the partitioned supplier profile again. That creates a new supplier profile without any issues.

Steps for importing the partitioned supplier profile:

1. Create the Supplier.csv and SupplierLocation.csv files.
2. Use the Import Suppliers task, and load these files using the Load option.

Core Procurement > Core Administration > Core Administration Import/Export
Core Procurement > Core Administration > Core Administration Supplier Management