Can I safely remove the usb drive?

July 11, 2008 7:40 AM

Can I safely remove my USB drive from a Windows computer without stopping it?

I always feel like I could save a few seconds by just removing the drive, instead of using the clunky "safely remove hardware" interface? If the drive isn't actively reading or writing, how big a risk is that?

posted by teaperson to computers & internet (14 comments total)

I almost always forget to unmount the thing and haven't had any problems.
posted by theichibun at 7:43 AM on July 11, 2008

One weird problem i encountered...

Sometimes I couldn't get my MacMini to recognise my USB drive... and then sometimes I couldn't get my Windows laptop to recognise it.

But if I plugged it in to the other machine it would always pick it up fine.

Turns out that stopping/safely ejecting the device before using it on the other machine cured the problem.
posted by saintsguy at 7:51 AM on July 11, 2008

it depends what you're running from it/on it, really. if you're only using docs, and you close them before removing the thing, then chances are you'll be fine
posted by ascullion at 7:52 AM on July 11, 2008

I've never had a problem just unplugging any flash drives (or turning off my digital camera) without unmounting first. Not sure if it's a good idea with regular spinning-platter external USB hard drives though.
posted by xbonesgt at 7:52 AM on July 11, 2008

Anecdotal evidence only, but I've always been fine with just unplugging it. I haven't had the dreaded 'delayed file write error' since I stopped using Zip discs years back (good riddance to those things). If I were copying some big & important files or running portable EXEs, I might take the time to unmount it. Then again, I might not.
posted by echo target at 7:58 AM on July 11, 2008

(These instruction are for Windows XP)

Go into device manager and right click the USB drive. Select the Policies tab and verify that it is set to 'optimize for quick removal'. This will allow you to remove it without stopping it.
posted by internal at 8:01 AM on July 11, 2008 [11 favorites has favorites]

The risk should be negligible provided, as you say, the drive isn't currently involved in reading or writing.

Having said that, I've had at least one (cheapo) USB stick that managed to corrupt itself whenever I forgot to remove it safely. Those I've acquired in the past year or two have all been absolutely fine though.
posted by le morte de bea arthur at 8:05 AM on July 11, 2008

Be default, USB storage is optimized for quick removal. What that means in practice is that write caching is turned off, so windows doesn't wait and keep stuff in memory waiting for the best time to write it to the drive. That also means that windows doesn't have to flush the cache before telling you it is safe to remove the drive.

Optimize for quick removal doesn't mean there will never be a write in progress when you pull out the drive, and if there is, you might loose data. You are probably safe if you wait until the drive hasn't shown any activity for 10-15 seconds.
posted by Good Brain at 8:11 AM on July 11, 2008 [1 favorite has favorites]

I dont recommend it. I used to have all sorts of problems with this until I religiously used that function. Perhaps not as often with flash drives but definitely with large external usb drives and mp3 players.

Considering how low the chances are you can probably get away with it but only if you have backups of those documents on that drive.
posted by damn dirty ape at 8:23 AM on July 11, 2008

Windows XP and later that's OK--due to the "optimize for quick removal" checkbox (no write caching or something). I would be careful nonetheless--specifically if you're writing things on the drive when you remove it (don't do that!).

HOWEVER Windows 2000 DOES require you to eject it before pulling it out (at least the last time I used it). Win2k does not have this new special quick-removal option. Ejecting will finish writing any cached items to the drive before removal.

Macs and Linux probably vary, due to the above write caching issue. Can't help you there.
posted by djpyk at 8:30 AM on July 11, 2008

I've never had an issue with it; I've been using the same USB keys, removable HDDs, and MP3 player for years without issues. I just unplug everything whenever I need it, although I do power-down the HDDs before removing them.

USB is fine, although you obviously need to be sure any data transfer operations have been completed. Just don't do it with FireWire, or anything that actually produces a current.

In the end, my advice is be as careful as the USB device's contents are important. MP3s you can copy over again, don't worry about it -- crucial backups generally should inspire a bit more dilligence.
posted by Dark Messiah at 9:42 AM on July 11, 2008

Does your USB drive have a status indicator light? Many do; it's just a little LED that flashes when data is being written to the drive. If the light is not flashing, you should have no problems pulling it out rather than ejecting it. After closing a file, I just wait a second, make sure the light is steady rather than flashing, and pull the drive out. Have had the same USB drive since 2005 and haven't lost any data on it yet from doing this.

Another note: In WinXP you can also right-click on the drive icon and just pick "eject" rather than use the clunky "Safely remove hardware" system tray thing. Win2k, you have to use the "safely remove.." bit. Not sure about Vista, I haven't had to use a thumb drive there.
posted by caution live frogs at 11:15 AM on July 11, 2008

Try this,

On your desktop create a new shortcut.
In the Target,
%windir%\system32\RunDll32.exe shell32.dll,Control_RunDLL hotplug.dll

In the Start In,
%windir%

Assign a Shortcut key,
Ctrl-Alt-Q

Place that in your Start Menu/All Programs and now, from anywhere you can hit the keystroke combination to initiate the Safely Remove Hardware dialog box.

I was never very good at taking the time until I found that shortcut somewhere.
posted by geekyguy at 12:03 PM on July 11, 2008 [5 favorites has favorites]

In Linux I always unmount the drive. Often IO operations are put on hold, so to speak, and even when the file manager lists the file as copied it may not be so.
posted by Monochrome at 1:34 PM on July 11, 2008