1. Your power is not plugged in properly, and the computer can't find the equipment you want.
2. There is something wrong with your driver;
The solution is:
1, plug it in again and see if the display light of your scanner or printer is on.
2. Open the Add and Remove Programs dialog box (double-click My Computer, open Control Panel, and then double-click Add and Remove Programs) to see if there are drivers for scanners and printers. If there is, you can delete it (maybe there is something wrong with the previous driver) and reinstall it.
If your scanner is used normally on other computers,
1, many scanners need to install drivers before connecting the USB cable and power supply, so it is better to plug the USB cable of the scanner back into the computer;
2. Try another USB port;
3. There is something wrong with the port and power supply.