In order to solve the issue, you can try to restart the devices. If you're using a USB connection, restart your computer and printer, connect the device and try to scan. If you're using a network connection, turn off your printer, your computer and your router and start them in this order: networking device, printer and computer. If it doesn't work, go to HP Support page, identify your printer model, select your operating system and download and install the latest drivers and software. Also, you can run the HP Print and Scan Doctor utility provided by HP. If it doesn't work, contact a HP technician. For further solution, you can check the official web page.