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Hi all I was wondering if I have to do a "safety USB removal" before shutting down the computer / hibernating (since I hardly shut down) the computer?

Or is it fine to simply hibernate the computer and (when the power is cut) unplug the USB ?

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up vote 4 down vote accepted

Pulling a USB device while shutdown is fine (it's actually probably the "best" time to do it).

Doing it while hibernated should be safe as well (as nothing will be writing to it while the system is hibernated), but may cause unexpected results at wake-up if there was an active program running from the now-missing USB device, or something had file handles open to data on it when hibernated.

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However what do you mean by while hibernating? When I initiate a hibernate, the screen immediately shuts down and the computers seems to run for another few seconds before quieting down. When should I pull out the USB? – Pacerier Jan 10 '12 at 16:51
By "While hibernated" I mean "While it is in a hibernated state", you should pull it once power has been cut (once the device is fully hibernated). – Ƭᴇcʜιᴇ007 Jan 10 '12 at 17:34

Part of the process of shutting down or hibernating (assuming this is not a hard shutdown where the power is cut) is making sure all of the devices are safely powered off.

As such, yes, you can remove the drive if the computer is powered off without worrying about it.

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Sry I don't get you.. when I hibernate the computer, the power is totally cut right? Or do you mean cut abruptly ? – Pacerier Jan 10 '12 at 16:36
Yes. Only if the shutdown/hibernation procedure does not complete sucsessfully might there be issues. When I said hard shutdown, I meant cord was pulled no battery, or holding down the power button. – soandos Jan 10 '12 at 16:38

You don't need to. Windows will check if there is any removeable devices on USB ports and will safelly turn off it before Windows shutdown. I usually remove Flash cards after shutdown if I want to shutdown and remove the Flash card after.

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Btw does it work properly with hibernating as well? – Pacerier Jan 10 '12 at 16:35
Im not sure that Windows will do the same on the hibernating process. Once a time I'v put my notebook to sleep with a flash card plugged on it, then I removed and inserted again, before turn on, on another USB port. After doing this, after returning from hib, my Windows alarmed me with a message about USB problems and crashed completelly. I made this another time to check if it was happening again but the error missed. – Diogo Jan 10 '12 at 16:40

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