Operating System Fundamentals and Troubleshooting Questions

Covers foundational operating system concepts and common platform level problems across desktop and server operating systems and how to diagnose and fix them. Fundamental areas include processes and threads, scheduling and priorities, virtual memory and swap, file systems and permissions, device drivers and system services or daemons, startup and boot processes, user account and permission models, and update and package management. Common issues covered are slow system performance, unresponsive applications, runaway processes, memory or handle leaks, filesystem corruption, driver or update failures, boot problems, permission errors, and networking or service failures. Candidates should be familiar with basic diagnostic techniques and tools for major platforms such as Windows, macOS and Linux including process and resource monitoring, log inspection, safe mode or recovery environments, system file checks, package and service management, and steps to roll back or isolate updates. Emphasize systematic troubleshooting workflows, evidence collection, and remediation strategies such as restarting services, isolating faulty drivers, correcting permission problems, cleaning up disk usage, and applying or rolling back patches.