1. Check your printer model and make sure it is compatible with printing from a USB or SD card.

2. Check your printer’s connection and make sure it is securely plugged into the computer.

3. Make sure all cables are connecting to the correct ports and there are no loose cables on either the printer or the computer.

4. Verify the driver for the printer is up to date and compatible with the computer and operating system.

5. Check to see if any pending updates are available for your operating system.

6. Check the printer settings, such as paper size and type, to make sure they’re correctly set.

7. Consult the user manual for the printer and verify that USB and SD card printing is supported.

8. Test the USB or SD card with another compatible device, like a digital camera, to make sure it is working correctly.

9. Restart the printer and the computer and then try printing again.