Many software failures are detected by z/OS and its components. These conditions are normally reported as system abends using a code consisting of the letter S identifying a system abend and three hexadecimal digits, for example, S0C4. Complete descriptions of these conditions can found in the IBM publications for your specific version of z/OS. If a system abend is reported for Mainframe Access, it is important to review the abend description. This will help you to make an initial determination as to whether this is most likely a Mainframe Access program failure or a failure caused by other system conditions that have affected the execution of Mainframe Access.