If you experience one of the following errors when scanning across a network on macOS:
Failed to open a connection to the device (-21345)
Failed to open a connection to the device (-21355)
Disabling IPv6 from the printer's control panel may resolve this issue.
Depending on your model, this will be found under LAN settings --> Common settings --> TCP/IP settings --> IPv6
OR
Device settings --> LAN settings --> Wi-Fi --> Manual setup --> TCP/IP settings --> IPv6
OR
Device settings --> LAN settings --> Wi-Fi --> Settings --> Advanced --> TCP/IP settings --> IPv6
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