You are getting the pop up because something is wrong, so that is what you need to address.
Have you tried the USB in different ports and/or with any other USBs unplugged, as sometimes you can get a conflict.
Do you get an Unknown device in Devices and Printers ?
Under USB Controllers in Device Manager right click on USB Root Hub, select Properties and under the Power Management tab check to see if the box is checked for allow computer to turn off this device to save power - if it is then uncheck it.
In Properties you can also see if there's a driver update available or unplug the USB and uninstall the Root Hub, reboot then plug the USB back in where it should reinstall the driver - but if you get the same problem with the USB on another machine then the USB has probably gone rogue.