warning HP

Error Code Wireless light blinks blue

Indicates the printer is disconnected from Wi-Fi or in setup mode.

? What Causes This

Printer not connected to wireless network or in Wi-Fi setup mode.

How to Fix It

Restart setup mode by pressing Power and Wireless buttons simultaneously, wait for Power button to flash, then release. The Wireless light will blink blue. Wait one minute and reconnect via HP Smart.

Source: page 2 of the official manual

From the manual

Manual page 2 — HP error Wireless light blinks blue

This error code appears in:

HP Deskjet Ink Advantage 2700 All-in-One Printer