Answer Description

The CompTIA troubleshooting methodology:

1. Identify the problem
2. Establish a theory of probable cause
3. Test the theory to determine the cause
4. Establish a plan of action to resolve the problem and implement the solution
5. Verify full system functionality, and, if applicable, implement preventive measures
6. Document findings, actions and outcomes

https://www.comptia.org/blog/troubleshooting-methodology