Problem ejecting USB Mass Storage device

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R2

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Having lots of fun configuring my scanners, the SDS100 being the newest
But having an issue with above.
After updating my 436 and the SDS100, when I go to eject the device, I get the dialog 'Problem ejecting USB Mass Storage Device.'
Goes on to say the device is in use, to close any program or windows that might be using the device.
My HP2 ejects without issue, its just the 436 and SDS100.
Anybody run into this, and have a solution?
I'm hesitant to close the Sentinel window or shut off the 436,
 

a417

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do you have a Windows Explorer window open that might have that drive path open on it? That's a common problem with USB devices and emulated storage. It sees an auto-opened My Computer window or an Explorer window as actively using the device, despite not actually doing anything with it.

Close ALL the windows.
 

R2

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The only open window was Sentinel itself.
I did close Sentinel, shut off the 436 and disconnected it.
Seems ok
 

RF23

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My present understanding is that it is important to “eject or dismount” USB devices via Windows before actually physically disconnecting them from the computer. The reason for this is that as the physical connection between the USB device and the computer is broken it will produce a spark, since a current is going from the computer to the USB device. Ejecting or dismounting the USB device turns off the power to the USB device and prevents this from happening. The spark quenching circuit in the USB device does not always work properly and this can allow the spark noise to be stored on the USB device’s memory. If this noise or corruption is on a disused portion of USB’s memory then it will not hurt anything, but if it in on your stored data it could cause your data to become corrupted. Worse of all is if the “spark noise” ends up on the part of the USB device’s memory that allows you to access the USB device then this could be very bad as the entire USB device may become inaccessible.
 

K7MFC

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My present understanding is that it is important to “eject or dismount” USB devices via Windows before actually physically disconnecting them from the computer. The reason for this is that as the physical connection between the USB device and the computer is broken it will produce a spark, since a current is going from the computer to the USB device.

This is wildly inaccurate. The reason for ejecting a usb drive is write caching. With write caching on, even if whatever you're transferring is done, there still may be data in the cache waiting to be written. Ejecting it sends the message to finish writing to the drive. Microsoft knows that people like to remove USB drives so Windows automatically disables write caching for removable flash drives. Ejecting the USB disk is not necessary on Windows.
 

Ubbe

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The eject function has nothing to do with the USB power. It only flushes any cache or buffers so that all data are transfered. You can check that by connecting a data cable to a mobile phone and then eject the USB port. The charging of the phone still continous from the 5v at the USB port.

/Ubbe
 

R2

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Ok, got it.
Been closing Sentinel, then disconnecting, seems ok.
Back when I got my 436 5 years ago, picked up a Windows laptop (I'm mostly a Mac guy) and back with Win8, I didn't eject it properly and it messed up a bunch of stuff. Spent an hour with Geek Squad fixing the problem. Once the tech figured it out, he was done in a couple of minutes.
 

kruser

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Per Microsoft- ejecting is not needed.


Maybe by default, write caching is disabled for removable USB or flash type drives and devices but it can still be enabled in Device Manager for almost any flash type device.
If someone enabled it, it will often remember that setting for a particular card or thumb drive and enable it again the next time it is inserted.

I still see this problem fairly often actually.
Look at a SD card or thumb drives Properties from Device Manager and make sure under Policies that no types of Write Caching are enabled or checked in the available options boxes for removable flash type devices.
The available Policies options explain which do not require the use of the Safe to Remove feature.
 

RF23

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My present understanding is that it is important to “eject or dismount” USB devices via Windows before actually physically disconnecting them from the computer. The reason for this is that as the physical connection between the USB device and the computer is broken it will produce a spark, since a current is going from the computer to the USB device. Ejecting or dismounting the USB device turns off the power to the USB device and prevents this from happening. The spark quenching circuit in the USB device does not always work properly and this can allow the spark noise to be stored on the USB device’s memory. If this noise or corruption is on a disused portion of USB’s memory then it will not hurt anything, but if it in on your stored data it could cause your data to become corrupted. Worse of all is if the “spark noise” ends up on the part of the USB device’s memory that allows you to access the USB device then this could be very bad as the entire USB device may become inaccessible.

Thanks guys for the update on the purpose of “ejecting USB devices”!

I stated “my present understanding” because I cannot remember where I got the info related to the power being turned off to the USB device when you eject it. It does appear this was incorrect.

Thanks again.
 
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