Using an Epson scanner with my Mac.

Power down both mac and scanner, check all connections.

Power up the scanner, restart the mac, open System Preferences> Printers & Scanners> Scan

does the scanner appear in the left hand panel. If so what happens when you press

Open Scanner…

wood0 wrote:

Can anyone help with the “Failed to open `a connection to device. error 21345” problem?

Check with Epson website for an updated driver for issues, and your particular printer & associated macOS.