Safely Remove External Drive

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Guest

When i click Safely Remove Hardware icon, I get following message:
The device 'Generic volume' cannot be stopped right now. try stopping the
device later.

How can i remove this drive?
 
When I occasionally get this message with my USB drive I just log off and
log back in. Once logged in again I can remove the drive.
 
When i click Safely Remove Hardware icon, I get following message:
The device 'Generic volume' cannot be stopped right now. try stopping the
device later.

How can i remove this drive?
Click to expand...

Something is accessing it.

Note that this can include the start directory of a program. If you
clicked on a file on the drive to run some program and that program is
still running the drive will still be locked even if the program no
longer is doing anything with the removeable drive.
 
Hi,

Go to My Computer, right click on the Ext. drive and then click eject from
the drop down menu.

Hope it helps.
 
bhm7319 said:
When i click Safely Remove Hardware icon, I get following message:
The device 'Generic volume' cannot be stopped right now. try stopping the
device later.

How can i remove this drive?
Click to expand...

From archive...

Usually at least one open handle to the drive prevents
the save removal.
Try to discover who has an open handle to your USB drive:

Get Sysinternals ProcessExplorer
http://www.sysinternals.com/Utilities/ProcessExplorer.html

Go to 'Find'->'Find Handle' and enter your drive letter like
U: and click 'Search'.

Then it lists all processes that hold open handles to your drive.


Greetings from Germany

Uwe
 
Tom said:
I believe deferred writes are turned off for removable drives by default.
So, it is actually safe to remove or turn off the drive witthout using
the safe remove icon/provisions.
Click to expand...

If the drive is NTFS fromatted then the write cache
is always activated.
Nonetheless, for greater certainty:

Navigate to Control Panel System Hardware Device Manager
Expand disk drives by clicking on the + Right mouse click on the drive
of interest Select Policies and select Optomize for quick removal.

That wil assure that deferred writes are off.
Click to expand...

No. For NTFS drives this is wrong. Try it!



Uwe
 
bhm7319
My external hard drive and flash drive does that when one of them has focus.
Double click My Computer and highlight the C:\ drive then go to saftely
remove hardware.
George
 
I believe deferred writes are turned off for removable drives by default.
So, it is actually safe to remove or turn off the drive witthout using
the safe remove icon/provisions. Nonetheless, for greater certainty:

Navigate to Control Panel System Hardware Device Manager
Expand disk drives by clicking on the + Right mouse click on the drive
of interest Select Policies and select Optomize for quick removal.

That wil assure that deferred writes are off.

If you find that the option is set here for performance and/or you prefer
to make it so, you should err on the side of safety and use the safe
removal facility or else only remove or shut the drive off when the
computer is powered off.


Tom
MSMVP
Windows Shell/User


: When i click Safely Remove Hardware icon, I get following message:
: The device 'Generic volume' cannot be stopped right now. try stopping
the
: device later.
:
: How can i remove this drive?
: --
: Thank you.
:
: Bharat
 
Tom said:
However, if you navigate to a
removable drive and repeat the selection of Policies, you will find that
the options to be Optimize for quick removal and Optimize for
Performance. Further, if you click on Restore defaults, the choice
moves to Optimize for quick removal. With that option, deferred writes
are off. Note in the text the statement, "This setting disables write
caching on the disk and in Windows, so you can disconnect this device
without using the Safe Removal icon." (Clicking the Safe Removal icon
causes Windows to complete all writes to the designated drive.)
Click to expand...

Yes, we all read it. But it has not tracable effect. Simple test:
Go to C:\Windows\inf
Click on the 'Size' column's header to sort by size. Mark the
about 30 smallest files and drag them to an USB flash drive.

If you can see how every single file is copied and the lamp
on the stick is hectic flashing and stops flashing as soon
as all files are copied, then there is no write cache.

If there is a write cache then the files are copied in a
'rush'. The stick's lamp will flash some seconds after
the Explorer finished the copy process.

Conclusion: Removable USB drives which are FAT formatted
have never a write cache while NTFS formatted ones have always.
Fixed USB drives which are FAT formatted are the only
ones the are affected by the removal policies, they
really get a write cache when 'Optimize for performance'
is selected.

I've put the results into a table:
http://www.uwe-sieber.de/usbstick_e.html
Nevertheless, I have made further inquiries and have some resources in
mind to check later because your query gave thought to another issue. Is
it possible that file handles and possibly other data structures will be
left in place that should have been closed before the drive is removed?
Click to expand...

I think ressources arn't the problem - we have enough
today :-) But when there are open handles on an USB drive
when the user wants to remove it then usually the user
forgot to close something and it's good to remember him
to do that before. But it's really sad that XP gives no
detailed information which processes hold open handles
to the drive.


Greetings from Germany

Uwe
 
Hi;

Thank you for your comment.



If you navigate as I indicated in my original post, to a non-removable,
NTS-formatted drive and click on Policies tab, you will discover that it
is set for Optimised for performance and that cannot be changed.
(There is the possibility of selecting Enable advanced performance
but write caching cannot be turned off.) However, if you navigate to a
removable drive and repeat the selection of Policies, you will find that
the options to be Optimize for quick removal and Optimize for
Performance. Further, if you click on Restore defaults, the choice
moves to Optimize for quick removal. With that option, deferred writes
are off. Note in the text the statement, "This setting disables write
caching on the disk and in Windows, so you can disconnect this device
without using the Safe Removal icon." (Clicking the Safe Removal icon
causes Windows to complete all writes to the designated drive.)



While I agree that "best practice" would dictate using "safe removal"
techniques and facilities or not shutting the drives off or removing them
until and unless Windows is properly shut down and the computer is
powered off, the question of the original poster was specific and not
directed to safe practice.



Nevertheless, I have made further inquiries and have some resources in
mind to check later because your query gave thought to another issue. Is
it possible that file handles and possibly other data structures will be
left in place that should have been closed before the drive is removed?
This is not an issue of possible file corruption but of un-reclaimed
resources. It's probably not a serious issue because Windows does better
'garbage collection' now. In days of yore, such things were the sole
responsibility of the programmers of individual applications rather than
a system function.



Tom

MSMVP

Windows shell/User

: Tom Ferguson wrote:
: > I believe deferred writes are turned off for removable drives by
default.
: > So, it is actually safe to remove or turn off the drive witthout
using
: > the safe remove icon/provisions.
:
: If the drive is NTFS fromatted then the write cache
: is always activated.
:
: > Nonetheless, for greater certainty:
: >
: > Navigate to Control Panel System Hardware Device Manager
: > Expand disk drives by clicking on the + Right mouse click on the
drive
: > of interest Select Policies and select Optomize for quick
removal.
: >
: > That wil assure that deferred writes are off.
:
: No. For NTFS drives this is wrong. Try it!
:
:
:
: Uwe
 
I had some problems with Norton's System Works which I have resolved except
that now my external USB causes the whole system to reboot when I turn it
off after using safe removal OK. The drive is a 40 MB drive formatted
NTFS. Any ideas why this might be occuring and any solutions. By the way I
took Sytem Works back and obtained a refund.

Cheers

Rod Gayford
 
First, I would make sure Norton System Works was completely removed. To
this end, navigate to
http://service1.symantec.com/support/nsw.nsf/docid/2001101612274407
and get the clean-up utility. Run that and let us know.

Tom
MSMVP
Windows Shell/User

:I had some problems with Norton's System Works which I have resolved
except
: that now my external USB causes the whole system to reboot when I turn
it
: off after using safe removal OK. The drive is a 40 MB drive formatted
: NTFS. Any ideas why this might be occuring and any solutions. By the
way I
: took Sytem Works back and obtained a refund.
:
: Cheers
:
: Rod Gayford
:
: : > Thank you again for your comment.
: >
: > : > : Tom Ferguson wrote:
: > : > However, if you navigate to a
: > : > removable drive and repeat the selection of Policies, you will
find
: > that
: > {snip}
: > : Yes, we all read it. But it has not tracable effect. Simple test:
: > : Go to C:\Windows\inf
: > {Snip}
: > : I've put the results into a table:
: > : http://www.uwe-sieber.de/usbstick_e.html
: > {Snip}
: > I'll have a look later when I can grab a few consecutive minutes.
: > :
: > : > Nevertheless, I have made further inquiries and have some
resources
: > in
: > : > mind to check later
: > {snip}
: >
: > : I think ressources arn't the problem - we have enough
: > : today :-) But when there are open handles
: > {snip}
: > I don't think one can ever have too many resources. ;-)) I have meade
: > some enquiries but don't expect anything back until early next week.
I am
: > not a systems engineer and have said everyting I can that I feel is
: > reasonable and accurate.
: >
: > If you are correct, Microsoft would be wise to make some revisions in
: > certain dialogue message text and recommended provisions and
procedures
: > for USB and other drive removal.
: >
: > :
: > : Uwe
: > :
: >
: > The device in question might be a USB HD. The poster is not specific
on
: > that point. However, that does not change the issue.
: >
: > Tom
: > MSMVP
: > Windows Shell/user
: >
: >
:
:
 
Thank you again for your comment.

: Tom Ferguson wrote:
: > However, if you navigate to a
: > removable drive and repeat the selection of Policies, you will find
that
{snip}
: Yes, we all read it. But it has not tracable effect. Simple test:
: Go to C:\Windows\inf
{Snip}
: I've put the results into a table:
: http://www.uwe-sieber.de/usbstick_e.html
{Snip}
I'll have a look later when I can grab a few consecutive minutes.
:
: > Nevertheless, I have made further inquiries and have some resources
in
: > mind to check later
{snip}

: I think ressources arn't the problem - we have enough
: today :-) But when there are open handles
{snip}
I don't think one can ever have too many resources. ;-)) I have meade
some enquiries but don't expect anything back until early next week. I am
not a systems engineer and have said everyting I can that I feel is
reasonable and accurate.

If you are correct, Microsoft would be wise to make some revisions in
certain dialogue message text and recommended provisions and procedures
for USB and other drive removal.

:
: Uwe
:

The device in question might be a USB HD. The poster is not specific on
that point. However, that does not change the issue.

Tom
MSMVP
Windows Shell/user
 
Tried the removal tool and it came up nil return so I must have got rid of
everything OK as I did go into the registry and deleted everything to do
with Norton or Symantec. However, I have solved the problem by obtaining an
update for my USB drivers. I believe NSW must have corrupted the drivers in
the first place.

Cheers

Rod Gayford
 
Great!

You hit on the second step which would have been to remove and reinstall
the USB support files. Some applications replace the MS-Supplied files
with their own. I am not familiiar enough with systemworks to say if it
does or not.

Glad it now works.

Tom
MSMVP
Windows Shell/User

: Tried the removal tool and it came up nil return so I must have got rid
of
: everything OK as I did go into the registry and deleted everything to
do
: with Norton or Symantec. However, I have solved the problem by
obtaining an
: update for my USB drivers. I believe NSW must have corrupted the
drivers in
: the first place.
:
: Cheers
:
: Rod Gayford
:
: : > First, I would make sure Norton System Works was completely removed.
To
: > this end, navigate to
: > http://service1.symantec.com/support/nsw.nsf/docid/2001101612274407
: > and get the clean-up utility. Run that and let us know.
: >
: > Tom
: > MSMVP
: > Windows Shell/User
: >
: > : > :I had some problems with Norton's System Works which I have resolved
: > except
: > : that now my external USB causes the whole system to reboot when I
turn
: > it
: > : off after using safe removal OK. The drive is a 40 MB drive
formatted
: > : NTFS. Any ideas why this might be occuring and any solutions. By
the
: > way I
: > : took Sytem Works back and obtained a refund.
: > :
: > : Cheers
: > :
: > : Rod Gayford
: > :
: > : : > : > Thank you again for your comment.
: > : >
: > : > : > : > : Tom Ferguson wrote:
: > : > : > However, if you navigate to a
: > : > : > removable drive and repeat the selection of Policies, you
will
: > find
: > : > that
: > : > {snip}
: > : > : Yes, we all read it. But it has not tracable effect. Simple
test:
: > : > : Go to C:\Windows\inf
: > : > {Snip}
: > : > : I've put the results into a table:
: > : > : http://www.uwe-sieber.de/usbstick_e.html
: > : > {Snip}
: > : > I'll have a look later when I can grab a few consecutive minutes.
: > : > :
: > : > : > Nevertheless, I have made further inquiries and have some
: > resources
: > : > in
: > : > : > mind to check later
: > : > {snip}
: > : >
: > : > : I think ressources arn't the problem - we have enough
: > : > : today :-) But when there are open handles
: > : > {snip}
: > : > I don't think one can ever have too many resources. ;-)) I have
meade
: > : > some enquiries but don't expect anything back until early next
week.
: > I am
: > : > not a systems engineer and have said everyting I can that I feel
is
: > : > reasonable and accurate.
: > : >
: > : > If you are correct, Microsoft would be wise to make some
revisions in
: > : > certain dialogue message text and recommended provisions and
: > procedures
: > : > for USB and other drive removal.
: > : >
: > : > :
: > : > : Uwe
: > : > :
: > : >
: > : > The device in question might be a USB HD. The poster is not
specific
: > on
: > : > that point. However, that does not change the issue.
: > : >
: > : > Tom
: > : > MSMVP
: > : > Windows Shell/user
: > : >
: > : >
: > :
: > :
: >
: >
:
:
 
I have received some comment from the enquiries I mentioned:

You are correct in that FAT and NTS volumes are treated slightly
differently.

For FAT, it does effectively turn off write-caching.

For NTFS, it changes the behavior but doesn't totally turn off the cache.
Worst case scenario is that writes less than 4KB can stay in the OS write
cache no more than half a second. All writes greater than or equal to 4K
pages are forced to be synchronized and not cached.

Also, this behaviour is partly determined by information in the device's
inf file. It is true of all consumer devices. For certain 1394
(firewire), non-consumer drives, adjustments are made.

So, in my view, while it is safe to remove consumer USB devices, best
practise still dictates that safe-removal facitities be used or the
system shut down before the device is disconnected or powered-off.

Tom
MSMVP
Windows Shell/User
 
om said:
I have received some comment from the enquiries I mentioned:

You are correct in that FAT and NTS volumes are treated slightly
differently.

For FAT, it does effectively turn off write-caching.

For NTFS, it changes the behavior but doesn't totally turn off the cache.
Worst case scenario is that writes less than 4KB can stay in the OS write
cache no more than half a second. All writes greater than or equal to 4K
pages are forced to be synchronized and not cached.
Click to expand...


That's very interesting. Accesses to the file system cause the
main performance inpact on flash drives because on flash drives
for each write access there must be read a block, erased, merged
and written back. That explains that even with 'optimized for
fast removal' NTFS gives a much faster feeling than FAT on flash
drives.

And it fits my observations: Lots of small files are copied
much faster while large files still as slow as the drive is.

But: The drive's lamp flashes by far more than half second
after the copy process finished in both cases and there doesn't
seem to be any difference beetween the policies 'optimized
for fast removal' and 'optimized for performance' on removeable
USB drives.


Greetinng from Germany

Uwe
 
I see similar symptoms---just do it twice. The first time it won't work
because the drive is spinning. The first attempt will turn off the motor. On
the second attempt, you can safely remove.

Mine usually actualy works first time ofthe drive motor has alreadt "gone
to sleep"-but if not, then just do the Safely Remove procedure twice
 
"The device 'Generic Volume' cannot be stopped because a program is still
accessing it." This is very very annoying...

You can also try to:
1) Open Task Manager and end the Explorer.exe process
2)Restart Explorer.exe process with Task Manager: select from menu File >
New Task (Run...) and write to input box "explorer"

I think it is possible to do this while you have other programs running.
 
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