A recent Windows update or a corrupted spooler file is the most likely cause. Run the Windows Print Troubleshooter (Settings > System > Troubleshoot > Other troubleshooters > Printer).
When requested, plug in the USB cable and turn the printer on. Windows or macOS should automatically recognize the device. Print a Test Page: Canon Printer F166 400 Driver
If you continue to see “F166” or “400” after installing the correct driver, focus on resolving network errors (for code 400) or hardware issues (for code F166). When in doubt, Canon’s customer support (1-800-OK-CANON in North America) can provide model-specific guidance based on your printer’s serial number. A recent Windows update or a corrupted spooler
Here is a comprehensive text regarding the driver, including how to identify it, where to find it, and how to install it. Windows or macOS should automatically recognize the device
series monochrome laser printer. Because "F166400" is not the primary marketing name, finding drivers on official support sites requires searching for the model instead. Key Driver Information Official Model Name: Canon imageCLASS LBP6030 / LBP6030w. Compatible Operating Systems: Windows 11, 10, 8.1, 7 (both 32-bit and 64-bit), and macOS. Primary Driver Types: UFR II/UFRII LT Driver: The standard driver for high-speed printing. XPS Driver: