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error HP
Error Code Printheads missing or improperly installed
One of the printheads is not present or correctly inserted into the printer.
? What Causes This
Improper installation or physical damage to components.
✓ How to Fix It
Ensure proper insertion and secure locking of both printheads, replace if damaged.
Source: page 9 of the official manual
From the manual
This error code appears in:
HP Smart Tank 510 Wireless All-in-One