External drive not showing in Device Manager

[alegator]

I have an external Lacie drive triple interface (USB2,FW400,FW800). I performed lately a Windows Repair to fix an issue with a printer which was successfull ("Disk1"). I also kept a 2nd drive with the original Windows installation before repair ("Disk2"). When I connect the Lacie to the PC with Disk1, windows won't pick it up (does not show in device Manager or My computer), but it can be used using the Firewire400. When I connect it to the PC with Disk2 the USB2 connection works normally. curious thing is that I also have a Seagate USB2 external drive and it works perfectly with Disk1. Is there something I can try to fix this issue without having to clean install windows? I went to Device Manager when the Lacie was connected using Disk2 and found that in "Driver File Details" the following files are listed, all in Windows\System32\Drivers: disk.sys, oodisr.sys, PartMgr.sys and snapman.sys.

[redwudz]

Do you have a 'Standard Enhanced PCI to USB Host Controller' showing in Device Manager under your USB controllers? The 'Standard Enhanced' part indicates a USB 2.0 controller. Though it would still work with a USB 1.1, just slower. I don't have a USB 2 controller in my XP computer and my other computer is running Vista, so your drivers don't match anyway. This is from USB 1.1



Since USB 2.0 is a add on, you might try installing fresh USB 2.0 drivers. Also, what's the drive letter for your external drive? I would make it a letter closer to the end of the alphabet so it has no chance of messing with your existing drive letter assignments.

[Krispy Kritter]

If you have access to the Administrative Tools, go to Computer Management. Under storage, there is a Disk Management section. This will show all of the drives found by Windows. My Computer and Windows Exporer only display drives that are initialized and ready for use. Drives found and recognized by the PC are listed in Disk Management. They won't show up elsewhere in Windows until they are properly initialized. This comes in handy for troubleshooting because if a HDD is not found in Disk Management or found in Disk Management but not Windows Explorer, then you are having a HDD issue. If the HDD is found in both, then you are likely having a windows issue.

You could try removing/deleting the USB controllers from Device Manager and reboot. This will force Windows to reload the USB devices and drivers. You could also verify and/or install the latest MB drivers, which should include USB drivers.

And then there is the obvious stuff, like a bad USB connector in the PC, a bad USB connector on the ext HDD, or a bad USB cable.

[alegator]

Do you have a 'Standard Enhanced PCI to USB Host Controller' showing in Device Manager under your USB controllers? The 'Standard Enhanced' part indicates a USB 2.0 controller. Though it would still work with a USB 1.1, just slower. I don't have a USB 2 controller in my XP computer and my other computer is running Vista, so your drivers don't match anyway. This is from USB 1.1. Since USB 2.0 is a add on, you might try installing fresh USB 2.0 drivers. Also, what's the drive letter for your external drive? I would make it a letter closer to the end of the alphabet so it has no chance of messing with your existing drive letter assignments.

Redwudz,these are the USB controllers I have:


I have XP SP2 so the USB2 drivers are native to Windows XP, they were installed with SP2. The drive letter for the Lacie is "L", it comes right after the "K" which is assigned to a removable disk (an external USB2 card reader).How do you change the drive letter of the Lacie if it is not recognized in the first place?

...if a HDD is not found in Disk Management or found in Disk Management but not Windows Explorer, then you are having a HDD issue.

Not true, as I stated above the HDD is perfectly fine (it works fine with Disk2), yet it does not show in My Computer, Device Manager or in Disk Management (Administrative Tools) when using Disk 1. So it is purely a software issue with Windows after being repaired.

And then there is the obvious stuff, like a bad USB connector in the PC, a bad USB connector on the ext HDD, or a bad USB cable.

As tests show, this is not a hardware issue, but purely a Windows one.

[redwudz]

The drive letters may be a long shot, but I tried changing one of my external drives to no letter and it disappeared from explorer, but it still showed up in Device Manager and Disk Management. I also added a memory card reader and it used up five of my drive letters, knocking one of my drives out of explorer.

You have a 'Enhanced controller' for USB 2.0, so that should be OK.

I agree, it's likely a software issue, but where? Is it in the drivers or something in the OS code that's messed up. I would try replacing the drivers, though.

A few more remote possibilities are some sort of IRQ conflict. Hard to check if you don't see the drive, though. Since the drive seems to work otherwise, it's probably not a firmware problem with the external drive controller.

And if you haven't done this, unplug all other USB devices as they could be a part of this.

Sorry, that's about all I can come up with. You might dig around on this site and see if they have any solutions: http://www.usbman.com/USB_Guides.htm

[Bjs]

No, its not an os issue, its your systems hardware causing the fault to appear .

One look at your pc specs spells trouble from a mile away .

Identify "addon" usb card ... and move it else where more suitable .

Never , ever , place a pci card in pci1 slot ... this is shared resource with agp slot and onboard video .

All pci slots from this point are "paired" , and only one from each group should have a pci card installed , not both .

[oldandinthe way]

Use the device manager to remove all of the USB drivers. Reboot and allow XP to detect the hardware and install the drivers.

[INFRATOM]

If windows assigns the same drive letter it would not show. right click on my computer left click on manage then disk management change assigned letter if you have more than one HD to high letters, so E to H would be free so if windows assign something would show up. your cd/dvd =D is ok. If your printer or else has card reader unplug them until you fix the letters.

[alegator]

Ok, so here is my current drive letter assignment (snapshot taken from "My Computer")

Drive letters "H" thru "K" belong to the Sandisk external Flash card reader, "C" is the main OS drive, "E" is the virtual drive used by Alcohol120%, "D" and "G" are the local DVD drives. So what is your suggested drive letter change? Thanks.

[redwudz]

I see two possibilities for problems there. Your virtual Alcohol drive may be messing with things and your Sandisk card reader is likely a USB device. I would temporarily remove the card reader and reboot and see if anything happens. And you might uninstall Alcohol and see if it changes anything. You can always reinstall it.

For drive letters, if you can get access to the external drive, I would change it's drive letter to 's' or a letter closer to the end of the alphabet. None of this may help, but it would at least remove a few possible causes.

I use 24 alphabet drive letters except 'a' and 'b' on one computer that has a internal card reader, optical and several internal hard drives and accesses my video servers with multiple mapped drives. With it, I can't add another external drive unless I delete one. I will probably just remove the card reader as I rarely use it and I have a external one if I need that function. With no open drive letters, a added drive won't show at all as I am using 'c' through 'z'.

[Krispy Kritter]

...if a HDD is not found in Disk Management or found in Disk Management but not Windows Explorer, then you are having a HDD issue.

Not true, as I stated above the HDD is perfectly fine (it works fine with Disk2), yet it does not show in My Computer, Device Manager or in Disk Management (Administrative Tools) when using Disk 1. So it is purely a software issue with Windows after being repaired.

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When a drive is found by Windows, it should appear in Disk Management. Until you can see it listed in Disk Management, it will NOT be assigned a drive letter and you cannot access the drive. Most common causes are hardware related. However, in the case of external drives, it's possible it is driver related.

As I noted above, delete/remove all of the USB related hardware in device manager and reboot. This will force Windows to reload the USB drivers and search for attached devices. You may also now want to take the time to ensure your motherboard and USB drivers are up to date.

[alegator]

I tested connecting the Lacie to the PC using the FW400 interface. windows assigned it the letter "L", so I went to Disk Management and changed the letter to "Z". All went fine. I then disconnected the Lacie and reconnected it using the USB2 but no success, drive not picked up by device Manager, Disk management or My Computer. So I guess I will proceeed with the Safe Mode cleanup. I'll keep you posted.

[alegator]

Well, I perfomed a safe mode USB cleanup and now the Lacie is normally recognized by the PC using the USB2 interface. One question though. I did the safe mode cleanup following the steps in this link: http://tinyurl.com/2fwb , but after restarting in standard mode Windows reinstalled the USB drivers by itself automatically, it did not prompt for the Windows OS Installation CD as the link instructions said so...?

[redwudz]

Then it's using your installed drivers from your HDD. They may have been corrupted or modified in some way by one of your programs. If they re-installed and it's all working, then all is good.

[alegator]

redwudz, yes, I was only wondering how come the problem was solved using the same files already in my PC Windows installation and not being refreshed by non corrupted files from the Windows CD. Anyway, I changed the drive letter of the Lacie from "Z" back to "L" and all is working fine. Also, the Seagate external is also connecting normally as before, with the letter "F". Thanks everyone for the hints.

[Krispy Kritter]

The corruption is often not with the actual drivers, but with the registry. Also, when adding many devices they install their own drivers thus causing issues. Deleting and rebooting restores the original OS drivers. Deleting and rebooting (you don't need to be in Safe Mode) the problem device(s) can also come in handy to fix many issues such as video and IDE drivers.