The biggest item to start the troubleshooting process is to understand the issue at hand. Clearly define what should be happening versus what is happening and gather information from the client about what their needs are. Next I would determine what the issue is, whether it be a technical issue that needs to be resolved or a possible user error. Then I would take the next steps to resolve the issue, whether that be completing the task myself, delegating it to a tech team, or sending the user detailed instructions.