Printer Shows as “Unknown Device” in Device Manager: Why and What to Do

# Printer Shows as “Unknown Device” in Device Manager: Why and What to Do

“Unknown Device” in Device Manager has a specific meaning: Windows successfully detected that something was connected, enumerated its hardware IDs, searched its driver database, and found nothing that matched. The device is recognized at the hardware level — USB communication is working — but Windows has no driver to assign to it.

This is different from a driver that’s installed but broken. “Unknown Device” means no driver, not a bad one.

Why This Happens with Printers Specifically

Most common hardware — network adapters, audio chips, USB hubs — has generic fallback drivers that Windows can load even when a specific driver isn’t available. Printers don’t have a reliable generic fallback. The closest thing is a generic PCL or PostScript driver, but those only work if the printer actually supports those page description languages, and many inkjet models don’t.

There are three situations that produce “Unknown Device” for a printer:

The driver was never installed and Windows can’t find one automatically. This happens most often with older printers or printers that use proprietary communication protocols. The printer connects, Windows searches Windows Update for a matching driver, finds nothing, and labels it Unknown Device. For HP DeskJet 2700 series and similar recent models, this shouldn’t happen — Windows Update has their drivers. For a Canon MX series printer from 2012, it can.

A driver was installed but the installation failed partway through, leaving the device in an uninitialized state. The printer may show as Unknown Device even though there’s a partial driver installation in the driver store. A failed HP Easy Start installation, for instance, can leave the USB composite device registered but the printer component stuck as Unknown.

The printer is connected via a USB hub or port that’s not providing enough power. Some older printers require consistent USB bus power during the enumeration phase. Connected through certain powered-down USB 3.0 ports or unpowered hubs, they don’t complete enumeration correctly and the hardware ID doesn’t transmit cleanly.

The Diagnostic

Right-click the Unknown Device entry → Properties → Details tab → Hardware IDs from the dropdown. You’ll see one or more strings like USB\VID_03F0&PID_2D17. The VID is the vendor ID and PID is the product ID.

Look up the VID first: VID_03F0 is HP, VID_04A9 is Canon, VID_04B8 is Epson, VID_04F9 is Brother. If the VID matches your printer’s manufacturer, Windows is seeing the printer but can’t identify the model.

Take the full hardware ID string to the manufacturer’s support page. Some manufacturers’ support pages let you search by hardware ID directly. If not, cross-reference the PID against a hardware ID database — usb.ids is a public database that maps VID/PID combinations to device names.

Once you know exactly which printer model the hardware ID belongs to, you can download the right driver.

The Fix

If the printer has been showing as Unknown Device since first connection (never worked): download the full driver package from the manufacturer’s site and run the installer before plugging in the printer’s USB cable. Most manufacturer installers are designed to be run first, then prompt you to connect the printer during the install process. Connecting first and letting Windows detect the device as Unknown Device, then running the installer, sometimes produces conflicts.

If the printer worked before and now shows as Unknown Device: the driver was likely removed or corrupted. Use the clean reinstall sequence: Device Manager → Uninstall device (with “Delete driver software” checked) → printui /s /t2 to remove any remaining driver package → restart Print Spooler → reinstall from the manufacturer’s full package.

If the USB connection is suspected (try other ports, try direct connection without a hub, check Device Manager for USB error codes under the Universal Serial Bus controllers section). A USB Selective Suspend setting in Power Options can also interfere with printer enumeration on restart.

When the Model Is Too Old

For printers where the manufacturer has stopped providing Windows 10 or Windows 11 drivers — and the hardware ID doesn’t match anything in Windows Update’s database — you’re in discontinued-model territory. The printer will show as Unknown Device permanently unless you find the right driver package.

PrintPro Driver Pro maintains an archived driver database for discontinued HP, Canon, Epson, and Brother models specifically for this situation. If you’ve confirmed the hardware ID is your printer but the manufacturer’s site shows no driver, that’s the tool I built to solve it. It doesn’t cover every printer ever made, but it covers most common US and EU market models from roughly 2010 onward.

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