I have an acer aspire laptop. Since using an external writer/reader two of my USB ports and my internal speakers no longer work. When I tried plugging in the external DVD writer the computer instantly shut off. I had used the external device at least a half dozen times before without issue. Upon reboot, the two ports it was plugged in to no longer function. I tried uninstalling and reinstalling the device driver software. As well as windows troubleshooting.