Most of the organizations not only compete in their field of expertise, but they also compete to be the leaders and the initiators of using modern applications and advanced technologies. Therefore, as the amount of data to be stored is inevitably increasing, the demand for faster data retrieval and sharing is getting higher and the level of security is becoming more critical. Most organizations enter the competitive world with the idea of keeping all their data on centralized computer systems. This enables the organization to automate the processes using which it carries out its operation more effectively and efficiently. In order to be able to achieve the accessibility and availability of data, the Operating Systems (OS) audit should be carried out carefully. The main focus of this research is to find out what are the issues involved in conducting information Technology (IT) auditing in banking sector of Oman, how these issues can be handled in accordance with IT audit standards. Case study is adopted from a real local bank in Oman, where OS auditing was carried out.