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We propose a network-coding based scheme to protect multiple bidirectional unicast connections against adversarial errors and failures in a network. The network consists of a set of bidirectional primary path connections that carry the uncoded traffic. The end nodes of the bidirectional connections are connected by a set of shared protection paths that provide the redundancy required for protection. Such protection strategies are employed in the domain of optical networks for recovery from failures. In this work we consider the problem of simultaneous protection against adversarial errors and failures. Suppose that ne paths are corrupted by the omniscient adversary. Under our proposed protocol, the errors can be corrected at all the end nodes with 4ne protection paths. More generally, if there are ne adversarial errors and nf failures, 4ne + 2nf protection paths are sufficient. The number of protection paths only depends on the number of errors and failures being protected against and is independent of the number of unicast connections.