unable to mount external hard drive

[mpdst11]

I am no longer able to boot my computer in Windows XP after it crashed when I was trying to update Windows.

I am trying to boot using a CD with the latest version of Knoppix just so that I can access my internal hard drive and copy some files to an external hard drive. I haven't had any trouble accessing the internal drive, but when I try to open the external drive, I get the following error:

Could not mount device.
The reported error was:
mount: I could not determine the filesystem type, and none was specified

I just bought the external hard drive for this purpose, and I am a total novice when it comes to Knoppix. Is there something I can do in Knoppix that will allow me to access the external hard drive?

[Harry Kuhman]

First of all, you should be able to mount the external drive under Knoppix if it's properly formatted and has not been corrupted by Windows when it died. Unfortunately, I have several NTFS external drives that Windows trashed and Knoppix can not mount them or recover files from them.

Second, f the external drive is NTFS then I would strongly advise that you do not try to write to it with Knoppix if and when you manage to mount it. Reading is safe, but writing to NTFS is not. There are some people who think that the newest version of Knoppix is safe to write to NTFS. There are others who say that there is some way to change with drivers Linux uses and the default is dangerous but their way is safe. For a new user I would advise against any of this unless the external drive is FAT formatted, which is safe to write to.

To mount the external drive partition (you actually mount the partition, not the drive) you should be able to just click on a partition that shows up on the desktop. Exactly what this partition will be named depends on what internal drives you have, their types of interface and how they are partitioned, and what type of external drive it is, how it is interfaced, and again how it is partitioned.

As an alternative to trying to write to a NTFS partition under Knoppix, I would suggest the folowing: Confirm that you can see the files that you want to recover with Knoppix on the internal drive. If they are there and you have a network available, install an FTP server on another system on the network (a Windows system is fine for this). Then use Konquror as an FTP client and transfer the files you want to save across the network to the other system. Once you have confirmed your backup, reformat and reinstall the corrupted Windows system.

Good Luck.

[mpdst11]

thanks Harry,

one of my problems is that the external hard drive is brand new, so I am not sure if it has been properly formatted or if it is NTFS or FAT.

however, i'm sure that it was not affected when windows crashed, because I had never used it before.

how can I tell if this drive is NTFS or FAT?

[Harry Kuhman]

• 1) Check the documentation that came with the drive.
  
  2) Search the Internet, Google is your friend (A.K.A. STFW).
  
  3) Post here what make and model it is, someone will likely know.
  
  4) I guess there is a small chance that the drive is not formatted at all, which would explain why Knoppix doesn't see a partition on it. (And there is a small chance that it's bad.) If there is nothing that you want on the drive then I would suggest formatting it as a FAT drive, which Knoppix can read and write just fine. The only issue that I can think of here is that FAT drives do have a file size limit, if you have files that are 4 gig in size or larger you can not copy them to a FAT partition. The Knoppix DVD ISO file itself, for example, can not be saved to a FAT partition. You can format it with Knoppix, but I seldom format under Linux except when I do it with the Deban installer, so I'm not going to risk making mistakes trying to talk you through it. I use windows or even DOS to fromat drives (usually with the Ranish utility), I suggest that if you have a working windows system available that you use that to both check if the disk is foratted and to format it as FAT if needed (remove the NTFS partition if require). If not go back to the Google is your Friend idea and ask it how to format under Linux, I''m sure that there are many good explinations already written.
  
  5) If you don't have a Windows system available to check the format of the disk (which seems unlikely), you should be able to determine it with the Linux utilities gpart or testdisk. I suspect that there are other ways as well, but these are the first that come to mind. If Knoppix can't mount the partition though I expect there may be problem, so I suggest you take the Windows approach in 4 above first.
  
  6) When people say they have an external hard drive we assume that they mean a drive attached by USB, firewire or external SATA connectors. But with the growing number of Network Attached Storage devices, it's rather important that we know what you are really talking about. You haven't said. If it's a NAS drive then ignore everything I've said here, you'll want to access it as a network drive, not mount it as a local drive.

[ckamin]

One other caveat worth mentioning. If you were to disconnect the drive from a system while it was writing to the drive, you could corrupt the drive. It happens quite often with Windows and commonly results in a RAW drive format. I've seen it all too often. I have seen it happen with Linux as well. It may only take a disconnect and/or reconnect once to cause it and could occur with a new drive if you are not careful. In Windows, the external drive should be stopped before disconnecting. In Linux, it must be unmounted first. This applies to drives connected directly to the system via USB, Firewire, eSATA, and even Ethernet. There have also been instances of drive corruption by Windows 2000/XP/Vista if the Fat32 partitions exceed 32 Gig in size. Linux apparently has no issues with larger Fat32 partitions.

You can possibly use a live Windows disk like Windows PE or Bart PE to check and format the drive to NTFS. If it is manufactured by one of the larger drive manufacturers, they may have a utility to check and format the disk. Some of these are bootable, but may not work well with external drives.

Harry's recommendations of attaching the drive to a working Windows PC may be a good idea and his advice is sound.