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Possible Duplicate:
USB slots stop working suddenly from time to time

The usb ports of my laptop fail for some reason from time to time. This concerns apparently mainly the external mouse and keyboard connected by usb, while connecting an external hard disk to the same ports may activate them. All gets back to normal after restart. How could I get the same effect without restart?

Since the issue reemerges after reinstalling OS and due to random variations I have created a new question asking for a permanent solution.. In case I get an answer I will close this one.

EDIT: /sys/module/usbcore/parameters/autosuspend contais only the line 2. /sys/bus/usb/devices/usb2/power/autosuspend and /sys/bus/usb/devices/usb3/power/autosuspend contain 0 (This was verified after solving the problem by restart, not before..)

I do not see Legacy USB Support in BIOS

I have edited and updated this question because I have some answers and comments here: but for new solutions please try answering my new question.

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marked as duplicate by cipricus, RolandiXor, Ringtail, Eliah Kagan, Jorge Castro Dec 29 '12 at 6:12

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

See if there is Legacy USB Support in your BIOS, and enabled it if its disabled. – Mitch Aug 20 '12 at 8:56
What's your Laptop brand? – Mitch Aug 20 '12 at 9:27
@Mitch - HP Compaq nx8220. I was asking about whether I should go into bios etc now I see that's what you ment – cipricus Aug 20 '12 at 9:39
@Rinzwind: did you mean the /sys/module/usbcore/parameters/autosuspend parameter? – izx Aug 20 '12 at 9:41
@cipricus Yeah, questions that are closed as duplicates are usually not deleted (whereas most other questions are deleted eventually). I'm out of close votes until the end of the day, but if you think it's a good idea for this question to be closed as a duplicate, I recommend flagging it for closure. – Eliah Kagan Dec 28 '12 at 21:35

Make sure that all USB devices are unplugged/safely removed and then try:

sudo modprobe -r usbhid && sleep 5 && sudo modprobe usbhid


sudo modprobe -r usb-storage
sudo modprobe usb-storage

This will reload the kernel modules for USB keyboards/mice and usb hdd's, and might emulate whatever it is about restarting that is fixing your problem. Good luck.

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sorry, nothing happens – cipricus Nov 6 '12 at 7:28

Another thing worth trying: restart the udev subsystem:

sudo restart udev

Tell us whether that one worked.

As for finding out what happens, I would start by going through the system logs. For example, when something like that happens, try

dmesg | tail

Otherwise, record the exact time, and later see in


for example by

gksudo gedit /var/log/syslog
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no, nothing happens – cipricus Nov 6 '12 at 7:29
happened again. reboot did not solve it, restart will. but before that (after reboot) i ran dmesg | tail and got this : – cipricus Nov 22 '12 at 15:24

a while ago I had the same problem with my openbox in Archlinux. This was due to laptop tools (or laptop mode tools) disabled the usb's after a few minutes of inactive.

The solution was to uninstall the package.

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laptop-mode-tools is not installed here – cipricus Nov 6 '12 at 8:13

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