If the device between your computer and MFP HP no connection, This might be due to usb printer problems, to solve printer USB connection problem try do the following :
Check the indicator On, on the front panel MFP HP. If the LED is not lit, the device MFP HP off. Make sure the power cord is firmly connected to the MFP, HP and plugged into the outlet. Press the On button, to turn on the MFP HP.
Check the cable USB. If you are using an older cable, it might not be working properly. Try connecting it to another device to see if the cable USB. If you have problems, you may need to replace the cable USB. Also make sure the cable does not exceed 3 meters.
Check the connection to the MFP HP computer. Make sure that the USB cable is securely connected to the USB port on the back of the MFP HP, and the other end of USB – the USB port on your computer. After checking the correct connection off and on again MFP HP.
If you connect the HP MFP to a USB hub, make sure that the hub is on. If the hub is on, try connecting directly to your computer.
Check other printers or scanners. You may need to disconnect older products from your computer.
Try plugging the USB cable to another USB-port. After checking the connection, restart your computer. Turn off and then again turn on the MFP HP.
If necessary, remove the software MFP HP and install it again.