CSV Import of Item Record Throws Error "Invalid item reference key"

Scenario

User is getting an error "Invalid item reference key" when doing a CSV import for an Item record and use Item Name as reference of the item on the Field Mapping Stage.

Solution

1. Navigate to Setup > Company > General Preferences
2. Unmark Checkbox Show Display Name with Item Codes
3. Click Save

Note: You can now successfully save the import after the above preference had been disabled.