5.0 - CompTIA A+ Core 1: How to Troubleshoot

How To Troubleshoot: Professor Messer

Troubleshooting process

1. Identify the problem/information gathering

   • Get as many details about the problem as you can - duplicate the issue, if possible.

   • Screenshot/write error messages/error screens on the user’s desktop.

   • Identify possible symptoms - burning smell, abnormal sounds, etc.

   • Question users for details

   • Determining if anything has changed from when the service/device/network was working (e.g., system patches)

   • Important: Approach multiple symptoms as their own problems.

   • Backup all information/have a rollback plan

2. Establish a theory of probable cause

   • Start with the obvious e.g., is the computer turned on?

   • Consult internal knowledge bases + Google searching

   • Make a list of all possible causes - start with easier ideas, then move on to harder ones

3. Test the theory and evaluate

   • Work through all theories of probable causes (i.e., your list from step 2), and check if one of them works.

   • If none work, re-establish your probable cause, contact a third party, or escalate.

4. Establish an action plan

   • Build a plan to correct the issue with a minimum impact/rollback plan.

   • Identify potential effects and create backup plans.

5. Implement the action plan

   • Fix the issue inside the assigned change control window. Escalate the problem if necessary.

6. Verify full system functionality

   • Use tests (typically defined at the start) to verify functionality. Also, have your customer confirm the fix.

   • Add preventative measures if applicable.

7. Document findings

   • Write findings in a knowledge base - don’t lose valuable info!

   • Note what actions you took and what outcomes were the result.