Hi. I'm David, and I'm happy to help you.
A USB connection is not necessarily required. The Epson ET-2870 can scan to your HP computer completely wirelessly, as long as both devices are connected to the same Wi-Fi network.
Go to the official Epson support page for the ET-2870 using the link below. Then, download and run the Drivers and Utilities Combo Package Installer.
Using this specific combo package is highly recommended because it automatically installs the necessary wireless network utilities alongside the essential scanning software, allowing your HP computer to detect the scanner over your network without needing a cable.
Feel free to ask any questions you may have.
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