External USB Hard Drive Doesn't Show


T

TMitchell

I have a new Seagate external USB hard drive that shows up in Device
Manager but not Windows Explorer (or anywhere else). I can hear the
Windows alert tone when it is connected and disconnected in Windows 7,
but cannot access the drive. It works fine on my XP system. (I tried
running SeaTools from Seagate to test the drive, but that app always
gives me a BSOD.) The drive works fine (as evident when I attach it to
my XP system, and I know my Win 7 system has enough power (1,200 Watt
power supply)for it .

Any ideas?
 
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Z

Zaphod Beeblebrox

On Fri, 11 May 2012 11:18:27 -0500, "TMitchell" <tmitche2
@ix.netcom.com> wrote in article
I have a new Seagate external USB hard drive that shows up in Device
Manager but not Windows Explorer (or anywhere else). I can hear the
Windows alert tone when it is connected and disconnected in Windows 7,
but cannot access the drive. It works fine on my XP system. (I tried
running SeaTools from Seagate to test the drive, but that app always
gives me a BSOD.) The drive works fine (as evident when I attach it to
my XP system, and I know my Win 7 system has enough power (1,200 Watt
power supply)for it .

Any ideas?
In Windows Explorer, go to Organize - Folder and Search Options - View,
and make sure that "Hide empty drives in the Computer folder" is
unchecked.

HTH
 
T

TLC

I have a new Seagate external USB hard drive that shows up in Device
Manager but not Windows Explorer (or anywhere else). I can hear the
Windows alert tone when it is connected and disconnected in Windows 7,
but cannot access the drive. It works fine on my XP system. (I tried
running SeaTools from Seagate to test the drive, but that app always
gives me a BSOD.) The drive works fine (as evident when I attach it to
my XP system, and I know my Win 7 system has enough power (1,200 Watt
power supply)for it .

Any ideas?
It may not have a drive letter assigned.

Click Start
Type diskmgmt.msc
Click on diskmgmt.msc

If your drive is listed, but doesn't have a drive letter, you will have
to assign a drive letter.
 
P

Paul

TMitchell said:
I have a new Seagate external USB hard drive that shows up in Device
Manager but not Windows Explorer (or anywhere else). I can hear the
Windows alert tone when it is connected and disconnected in Windows 7,
but cannot access the drive. It works fine on my XP system. (I tried
running SeaTools from Seagate to test the drive, but that app always
gives me a BSOD.) The drive works fine (as evident when I attach it to
my XP system, and I know my Win 7 system has enough power (1,200 Watt
power supply)for it .

Any ideas?
Have you tried:

Start : diskmgmt.msc

Look in Disk Management, and see if a partition is present on it.
If not, create a new partition.

*******

And just because you have a 1200 Watt supply, that means nothing
with respect to a USB port. The USB port is protected by a Polyfuse,
and that is only rated for 1.1 amps or so. Depending on the load
present on the other port in the USB2 stack, the Polyfuse could open
and remove the source of power to the 2.5" USB drive. The fuse
closes again, when it cools off.

A 3.5" hard drive, typically has an external power source. And in
that case, only a couple milliamps flow from the USB Vbus power source.
A 3.5" hard drive, should not have powering problems.

A 2.5" hard drive, typically draws all its power from the USB Vbus. A
2.5" drive can draw 1 ampere for ten seconds, during spinup. Some
motherboards can't take the load, and the Polyfuse opens before
spinup is complete. Or, depending on your cabling, if there
is sufficient voltage drop in the cable, that can cause the
drive to spin down and spin up, over and over again.

- Use a short, fat USB2 cable, of good quality, not a keyboard cable.
- Only place one load on a "stack of two", until the drive is detected
and you know it works. The purpose of that, is to reduce any other
potential USB loading on the stack of two. Running two 2.5" drives
from a single USB stack of two, is not recommended.

The +5VSB rail of the 1200W supply, could be rated for 2 to 3 amps.
Which means only 10W to 15W of the 1200W is available on that rail.
So the rest of the 1200W hardly matters. The fact you could use
that supply for arc welding, doesn't change the fact the +5VSB
rail that runs external USB, is weak. If you plug enough 500mA USB
loads in, eventually any supply will switch off. (Because the +5VSB rail,
seldom provides more than 3 amps.) All it would take, is three to six
USB2 2.5" hard drives, to cause the power supply to shut off. The computer
would try to POST, and would shut down about two seconds later.

*******

If the partition is present after all, another issue that arises is
"Take Ownership", to actually do something with the files. You'll
find many web pages on the issue.

http://www.howtogeek.com/howto/wind...ership-to-explorer-right-click-menu-in-vista/

Paul
 
T

The Seabat

You might want to check your BIOS and make sure that AHCI has been
enabled. Just sayin'.
 
P

pjp

tmitche2 said:
I have a new Seagate external USB hard drive that shows up in Device
Manager but not Windows Explorer (or anywhere else). I can hear the
Windows alert tone when it is connected and disconnected in Windows 7,
but cannot access the drive. It works fine on my XP system. (I tried
running SeaTools from Seagate to test the drive, but that app always
gives me a BSOD.) The drive works fine (as evident when I attach it to
my XP system, and I know my Win 7 system has enough power (1,200 Watt
power supply)for it .

Any ideas?
No one has mentioned this so ...

Under Control Panel/Administrative Tools/Computer Mangement choose Disk
Management in left hand pane.

Is the drive shown? If not likely hardware problem but assuming it is
seen (beeps indicate that) there's a couple of possibilities. You may
need to initialize the drive, is there a partition on the drive, is it
formatted? Likely there is a partition and it is formatted and all you
need to do is Initialize the drive. Unsure which right click that's
found under. There's three possibilities. Right click on drive in top
pane or on one of the two "boxes" in bottom pane.

Seem to remember one of my externals acted in a similar manner to what
you describe and "Initialize" took care of it.
 
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Z

Zaphod Beeblebrox

On Fri, 11 May 2012 12:58:28 -0500, "The Seabat"
You might want to check your BIOS and make sure that AHCI has been
enabled. Just sayin'.
I don't think that the AHCI setting would have any effect on an
external USB drive. Just sayin' :)
 
C

croy

I have a new Seagate external USB hard drive that shows up in Device
Manager but not Windows Explorer (or anywhere else). I can hear the
Windows alert tone when it is connected and disconnected in Windows 7,
but cannot access the drive. It works fine on my XP system. (I tried
running SeaTools from Seagate to test the drive, but that app always
gives me a BSOD.) The drive works fine (as evident when I attach it to
my XP system, and I know my Win 7 system has enough power (1,200 Watt
power supply)for it .

Any ideas?
Do you have any mapped drives? If so, have you mapped any
drive to the letter "Z"? If so, there is a Microsoft
KnowledgeBase article about the problem. I don't have a
link on this machine, but if you do enough searching, you'll
find it.

As I recall, if the two conditions above are met, Windows
will try to assign the new USB drive to a letter that it
already used. I seem to recall that in Explorer, you'll see
that one of the drive letters you're used to seeing will
show the contents of the USB drive, and you won't be able to
see the contents of the internal drive that originally held
that drive letter.

No guarantees on my memory!
 
Y

Yousuf Khan

You might want to check your BIOS and make sure that AHCI has been
enabled. Just sayin'.
Completely irrelevant. A USB drive doesn't use AHCI drivers, it uses USB
drivers.

Yousuf Khan
 
Y

Yousuf Khan

No one has mentioned this so ...

Under Control Panel/Administrative Tools/Computer Mangement choose Disk
Management in left hand pane.
Actually, I think everyone has mentioned this so far, in some variant or
another. This is the same as running "diskmgmt.msc".

Yousuf Khan
 
P

pjp

Actually, I think everyone has mentioned this so far, in some variant or
another. This is the same as running "diskmgmt.msc".

Yousuf Khan
Yea but I saw nothing about "Initializing" the drive so excuse me for my
$0.02 :)
 
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Y

Yousuf Khan

Yea but I saw nothing about "Initializing" the drive so excuse me for my
$0.02 :)
Actually, initializing the drive would make things worse for him.
Initializing the drive would require wiping the partition table off the
drive and recreating it. :)

Yousuf Khan
 
P

pjp

Actually, initializing the drive would make things worse for him.
Initializing the drive would require wiping the partition table off the
drive and recreating it. :)

Yousuf Khan
I don't remember that as the scenario when I had to do it for the 2T
Seagate external I connected. It was already partitioned and formatted
but I had to Init it before Windows would assign a drive letter to it. I
remember because I had to hunt-n-peck for which "box" I had to right
click on to get that option. Don't remember it then patitioning and
formatting it afterwards. Mind you it was awhile ago now and I am 60+ :)
 
Y

Yousuf Khan

I don't remember that as the scenario when I had to do it for the 2T
Seagate external I connected. It was already partitioned and formatted
but I had to Init it before Windows would assign a drive letter to it. I
remember because I had to hunt-n-peck for which "box" I had to right
click on to get that option. Don't remember it then patitioning and
formatting it afterwards. Mind you it was awhile ago now and I am 60+ :)
The stages of making a hard disk ready for data are: (1) initializing
(creating the partition table itself), (2) partitioning (choosing the
locations where various filesystems are going), and (3) formatting
(creating the filesystems).

Yousuf Khan
 
L

Leon Manfredi

On Fri, 11 May 2012 12:58:28 -0500, "The Seabat"


I don't think that the AHCI setting would have any effect on an
external USB drive. Just sayin' :)
USING MINE WITH, ACRONIS.... both IMAGE and DIRECTOR...
 
L

Leon Manfredi

On Fri, 11 May 2012 12:58:28 -0500, "The Seabat"


I don't think that the AHCI setting would have any effect on an
external USB drive. Just sayin' :)
SIMPLE CURE..... ASSIGN A DRIVE LETTER TO IT AND IT WILL BECOME VISIBLE IN
EXPLORER.....
 
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B

BillW50

Leon Manfredi said:
SIMPLE CURE..... ASSIGN A DRIVE LETTER TO IT AND IT WILL BECOME
VISIBLE IN EXPLORER.....
Are you restoring from an USB drive with Acronis? Some USB controllers
it won't work. Most of mine it won't (no other backup software has this
problem except Acronis). And this problem starts well before 2007 and
continues at least up to 2011 version for sure. If you ask ATI support
they tell you to use an internal drive instead. And this to me is a
worthless answer since it is the internal drive you want to restore.
 
T

The Seabat

Opps! You're right. My drive was hooked up via eSATA. My bad. On my
behalf I do suffer from a bad case of C.R.S.!
 
J

J. P. Gilliver (John)

In message <[email protected]>, Yousuf Khan
The stages of making a hard disk ready for data are: (1) initializing
(creating the partition table itself), (2) partitioning (choosing the
locations where various filesystems are going), and (3) formatting
(creating the filesystems).

Yousuf Khan
Do discs often come with (1) already done these days?
 
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A

Andy Burns

J. P. Gilliver (John) said:
Do discs often come with (1) already done these days?
IME no, but they do come with (0) low level formatting (creating the
tracks/sectors themselves) already done.
 

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