Direct answer
Upside-down backs usually mean the duplex binding edge is wrong: flip on long edge versus short edge. Orientation and app print dialog both matter.
What this covers
- The observed symptom matches this record
- Customer-accessible settings, connections and external components
- Diagnosis before reset, deletion or component replacement
What it does not cover
- ×A model-specific error code with a different documented meaning
- ×Internal electrical, battery-cell, gas, refrigeration or sealed-component repair
- ×A guarantee that every model exposes the same control label
Capture the exact symptom
ReversiblePrint a two-page test marked TOP on each page and note portrait or landscape orientation.
Run the smallest isolation test
ReversibleSwitch only the long-edge/short-edge binding option in the app or driver, not page rotation and scaling together.
Correct only the proven cause
ReversibleSave the correct preset separately for portrait and landscape jobs.
Verify before changing anything else
ReversiblePrint the marked test again and confirm both sides read in the intended book or calendar direction.
Evidence ledger
Sources behind this answer
Visible sources support the visible claims. Home Product Support records the publisher, the fact used and the review date; community reports can suggest an issue but do not become a published fact on their own.
Exact questions
Common follow-ups
What should I check before resetting anything?+
Print a two-page test marked TOP on each page and note portrait or landscape orientation.
What is the safest isolation test?+
Switch only the long-edge/short-edge binding option in the app or driver, not page rotation and scaling together.
When should I stop troubleshooting?+
No hardware reset or service is needed when the printer duplexes mechanically.
Answer for the exact device and software version shown above.