Symptoms
- Computer doesn't show any new device when the printer is plugged in via USB
- 'Unknown device' or driver error appears in Device Manager
- Printer worked before on the same cable and port
- Printer is detected on a different computer
Likely causes
- CommonFaulty or low-quality USB cableUSB cables can wear out or be poorly made, especially longer or cheap ones.
- CommonUSB port issue on the computerA specific port might be damaged, powered down, or have a driver conflict.
- CommonPrinter driver not installed or corruptedWithout the correct driver, Windows may not properly recognize the connected printer.
- PossiblePrinter not powered on before connectingSome devices need to be powered on first for proper USB enumeration.
What to do
- Confirm the printer is powered on before checking the USB connection.
- Try a different, known-good USB cable, ideally a shorter one if the current cable is long.
- Plug the USB cable into a different port on the computer, preferably directly on the computer rather than through a hub.
- Check Device Manager (Windows) for the printer under 'Printers' or 'Universal Serial Bus controllers,' and note any yellow warning icons.
- Uninstall and reinstall the printer driver from the manufacturer's website.
- Test the same USB cable and printer on a different computer to isolate whether the issue is the cable, the printer, or the original computer.
Tools and parts
- None
USB printer cableSearch: “USB A to B printer cable”
When to call a pro
If the printer isn't detected on any computer with a known-good cable, its USB port or internal circuitry may have failed and needs professional evaluation.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.