As one of the emerging services in cloud paradigm, cloud storage enables users to remotely store their data into the cloud so as to enjoy the on-demand high quality applications and services from a shared pool of configurable computing resources. While cloud storage relieves users from the burden of local storage management and maintenance, it is also relinquishing users’ ultimate control over the fate of their data, which may put the correctness of outsourced data into risks. In order to regain the assurances of cloud data integrity and availability and enforce the quality of cloud storage service for users, we propose a highly efficient and flexible distributed storage verification scheme with two salient features, opposing to its predecessors. By utilizing the homomorphic token with distributed erasure-coded data, our scheme achieves the integration of storage correctness insurance and data error localization, i.e., the identification of misbehaving server(s). Unlike most prior works, the new scheme further supports secure and efficient dynamic operations on outsourced data, including: block modification, deletion and append. Extensive security and performance analysis shows the proposed scheme is highly efficient and resilient against Byzantine failure, malicious data modification attack, and even server colluding attacks.