Cannot insert duplicate key row - Replication

• 2601 Cannot insert duplicate key row in object '%.*ls' with unique index '%.*ls'
• 20598 The row was not found at the Subscriber when applying the replicated command.
• 2627 Violation of PRIMARY KEY constraint 'PK__A'. Cannot insert duplicate key in object 'dbo.A'.

http://www.mssqltips.com/sqlservertip/2469/handling-data-consistency-errors-in-sql-server-transactional-replication/