Hardware Troubleshooting

• If the video display fails, first make sure the monitor is plugged into the correct socket on the computer. Next test the monitor with a good signal from another source. Next, an appropriate video card can be swapped out. Obtain a CD to test all aspects of hardware up to a point. Hardware fails because of motherboard errors, hard-drive issues and issues such as the hard-drive data cable is loose, reversed, or disconnected. The power cable may be loose or disconnected. It may fail to spin up. There may be a failure of the hard drive's bottom board or it may be full to capacity.
  
  Many hardware components can be swapped out. Remember, swapping out components is the best way to arrive at a decision about a certain component. Components that can be swapped out are the keyboard and mouse. But remember that on a network, both the keyboard and mouse can be subject to registry misconfiguration.
  
  The mouse could be subject to hardware board failure or other breakages of delicate internal components. Another issue with mouse workings is that an optical mouse may fail to work because the signal is being reflected back from an ultrashiny surface.
  
  

Network Troubleshooting

• Verify the physical connection to the local network. Ensure that the cable is not loose or unplugged, or the termination isn't worn. There could be a bad socket or a bad port on an intermediate piece of hardware like a switch or router. Check for protocol errors. These include TCP/IP errors such as misconfigured stack or domain name system (DNS) errors.
  
  Work outward. Ping the localhost by using the Windows command "ping" and the "127.0.0.1" address. Ping a known website and see whether you can get out to it. If it's unreachable, check the DNS settings and use a known good DNS server if the DNS is set to automatic. The Internet service provider's network or office LAN could be down for everybody, but this is less likely.
  
  

Operating System Troubleshooting

• If you receive an operating system error, it's likely that the system has encountered a bad piece of code in a recently installed software package. Also, a driver update may have caused a commonly shared software component, such as a DLL (library file) or Visual Basic extension, to be overwritten. Think back to the most recent thing that happened on the system or the most recent driver update or the latest software installation. If possible, use System Restore to roll back to the period before the event. This is a useful tool in troubleshooting, since nearly all troubleshooting is ruling out issues and narrowing down the root cause of a problem.
  
  

Software Troubleshooting

• Software can be tested using a variety of free tools. One is the Process Monitor (see References). This tool let a troubleshooter test software while it's running, permitting flawed software to indicate exactly what software or registry key changes are taking place at the precise time. For example, an audio port is activated when a signal is received in a voice-over-IP telephone software package. The Process Monitor can track changes in the audio port so that the precise moment this occurs can be verified.