System Configuration: Acer Aspire S7-391 with 256GB SSD, 4 GB RAM, 2 USB 3.0 ports, Win 8.1.

Problem: I recently started noticing the CPU running at 100% whenever I plug in a usb storage device. I also noticed that when a usb storage (any type, even a modem with little storage space) is plugged in, a new explorer.exe starts up along with the existing one and both the processes take up 50% each. When I stop both the explorer processes and restart the explorer.exe everything comes back to normal. So I literally have to keep the taskbar open to kill the explorer processes whenever i plugin my external HDD or my modem! I have been using the machine for the past 10 months with all important updates installed over time. The machine is also free from virus (Windows Defender updated).

Any help would be much appreciated.

Thanks.

• Edited by Vivek2209 Friday, March 07, 2014 7:11 AM

Hi,

Lets narrow down this issue via following steps:

1. Boot into Clean Boot mode to test if this issue persists, this would eliminate the software conflicts.
2. Reinstall the USB controller driver.

Hi Alex,

I have done a clean reboot and looks like now there is no recurring explorer.exe or cpu taking 100%. However I have not reinstalled the USB Controller driver yet. When I tried uninstalling, I had to go through reboot process and when it restarted the USB controller driver was still there. Do I continue starting the computer with clean boot mode or do I have to change back to the normal boot up?

Thanks,