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error HP
Error Code Error Icon ( ) blinking
Indicates an unknown error requiring user attention.
? What Causes This
Various issues like paper jams, out of ink warnings, or system errors can cause this icon to blink.
✓ How to Fix It
Refer to control panel display for specific error message and solution steps. Press resume button if applicable.
Source: page 2 of the official manual
From the manual
This error code appears in:
HP Ink Tank 315