This guide begins with an introduction to LAN troubleshooting. We will review the troubleshooting process and the eight steps to successful troubleshooting. Next, will be information on troubleshooting physical layer problems. We will cover twisted-pair copper and fiber optic media. Advice on troubleshooting common network user complaints will follow. Common complaints include user connection issues and slow networks. The guide concludes with an in-depth discussion of troubleshooting switches. We will describe many switch troubleshooting methods. Frontline LAN troubleshooters who learn how to apply these methods will be able to solve network problems fast.