IT SYSTEMS IN PLAIN ENGLISH
See the whole system. Find the real problem.
https://itsystemsinplainenglish.com/

TROUBLESHOOTING FIELD NOTES

Date / time / time zone:
Reported symptom:
Expected outcome:
Actual outcome / exact error:
Affected people / devices / locations:
Known working comparison:
Recent relevant changes:

THE REQUEST PATH
User -> browser/app -> computer -> network -> service -> dependencies
Adjust the map to the system you are investigating.

FOR EACH CHECK
Test and where it ran:
Time:
Result:
What it supports:
What it does not cover:
Next question:

THE HANDOFF
Summary and scope:
Evidence collected (redacted as needed):
Working vs failing differences:
Changes already made and authorization:
Next unanswered question:

VERIFY AND LEARN
Original user action repeated:
Outcome:
Evidence for cause:
Useful habit or documentation change:

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