The Troubleshooting theory 902 Exam: Given a scenario, explain the troubleshooting theory MM Video 3:35

Computer Problems Troubleshooting computer problems is a part of the computer technician’s role Before you can fix a computer problem, you need to identify its cause Expert troubleshooters use a systematic method to solve any computer problem Every day there will be new problems to solve Then ensure the steps you take successfully resolve the problem Following this approach helps identify and resolve problems as efficiently as possible

To diagnose and troubleshoot a problem appropriately, you should perform the following steps in sequence: Interview the user, identify the problem, and perform a backup Establish a theory of probable cause Test the theory to determine the cause Establish a plan of action and implement the solution Verify full system functionality Document your findings, actions, and outcomes

Step 1: Identify the Problem Some good questions to ask the user: Describe the problem. What error messages, unusual displays, or failures did you see? When did the problem start? What was the situation when the problem occurred? What programs or software were you using? Can you show me how to reproduce the problem? Has someone else used your computer recently? What system changes have been made?

Step 1: Identify the Problem When you try to access Google.com, your computer contacts its DNS server and asks for Google.com’s IP address. You can try accessing a website at its IP address directly, which bypasses the DNS server. If the IP address method works but you still can’t access google.com, it’s a problem with your DNS servers. Step 1: Identify the Problem If you see packet loss (in other words, if the web server didn’t respond to one or more of the packets you sent), this can indicate a network problem. Many problems occur due to recent action, so its important to find out from the user if anything has changed Think of the user as a partner in your quest to resolve the problem If the user is in an environment with other users, its good to find out if they’re having the same problem If not, the problem is likely with that user’s system, but if its affecting all users, the problem is likely a network problem Once you identify the problem, it’s important to back up the computer’s hard drive to ensure no data is lost

Step 1: Identify the Problem When restarting a computer or when a computer is switched on, it runs a power on self test (POST) POST is a useful tool for determining problems with system hardware A good practice is to restart a computer so it’s in a clean state before troubleshooting further If the POST detects a problem, the BIOS may give you a visual message or audio response (beep codes) If the POST completes successfully, you’ll need to gather more info from the user

Step 2: Establish a Theory In middle school or high school you learned about the scientific method Scientists develop a hypothesis, test it, and then figure out if the hypothesis is valid Step 2: Establish a Theory Troubleshooting involves much the same process Theories can either state what can be true or what can’t be true Start eliminating possibilities and eventually the only thing left is what’s wrong (or the issue) Start broad and narrow your scope

Step 2: Establish a Theory The info a user provides can help with isolating the probable cause of a problem Verifying the actions that a user performed before the problem happened may reveal the problem type You may find that the issue is hardware related, software related, or user error Make your best guess as to the source of the problem Example: If video does not work, a best guess is the monitor cables are loose or the monitor is turned off

Testing your theory involves: Step 3: Test Your Theory Once you identify the problem and possible cause of the problem, continue the process and test your theory Testing your theory involves: Checking that the system is connected to a power source Checking hardware and software configurations Checking Device Manager Checking Vendor documentation Checking Log files for entries related to the problem Isolating the problem

You should ensure the power supply is connected and turned on CHECK HARDWARE & SOFTWARE CHECK THE POWER SOURCE You should ensure the power supply is connected and turned on If a hardware problem is suspected ensure that the specific hardware is connected should be a first step Power cables can become disconnected without the user realizing it and checking for obvious causes saves a lot of time If a software problem is suspected check that the proper software and device drivers are installed

CHECK DEVICE MANAGER CHECK VENDOR DOCUMENTATION Use Device Manager to check for conflicts between hardware devices and other problems with hardware Vendor documentation often includes a list of problem symptoms and related fixes Devices with an exclamation or found under other devices indicate that the device is conflicting with other hardware or the drivers for the device are not installed properly Explanations can usually be found for status lights, indicators, and other visual clues that can help in the troubleshooting process

You can use Event Viewer to access log files for the computer ISOLATE THE PROBLEM CHECK LOG FILES You can use Event Viewer to access log files for the computer A common technique is to strip the system down to the bare bones and then slowly rebuild the system to see if the problem comes back Event Viewer is like the Windows “tattletale program” as it will show you what has happened in the last day, week, month, or more To isolate a software issue, stop all nonessential services running in the background or start Windows in Safe Mode to eliminate unnecessary startup programs and drivers

Step 4: Establish a Plan of Action Once you confirm the cause of a problem, the next step is to establish a plan of action and implement the solution Consider different solutions and select the least invasive If you implement a change and it doesn’t resolve the problem, you should undo the change Example: If you suspect a faulty hardware component, exchange the bad component with one that you know is working You may solve the initial problem but create a host of other problems if you don’t undo any changes made

Step 5: Verify full system functionality Once you implement a solution, restart the system and verify full system functionality It’s important to test the whole system, rather than only the hardware or software you’ve fixed or replaced This ensures there has been no adverse effects on other parts of the system Have the user check everything and verify functionality as well Ask yourself this question: Could this problem have been prevented? If so, instruct the user on what to do (set Windows to automatically install updates, advise on proper cooling)

Step 6: Document What Happened It simplifies troubleshooting the next situation Finally, document the actions you took in correcting the problem as well as the outcomes of those actions Many companies use help desk software to record and track troubleshooting activity in tickets Reasons to document include: It helps with training others It develops effective preventative maintenance plans