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I want to format my pc from DOS while the operating system fall and the type of drives are NTFS.

When I try to format it these messages appear:

invalid drive specification
   format not supported in drive C:
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migrated from Mar 17 '11 at 13:21

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Remove NTFS file system and Reformat with Win 98/Me Boot Disk

Format with a Win98/Me Startup disk.

Use a Windows 98/Me startup disk to delete the non-dos partition. Boot from Startup Disk.

Load FDISK by typing "fdisk.exe" at the "A" prompt without the quotes.

Say yes to large disk support ...........? [Y] ENTER

Enter choice #3 to "Delete partition or Logical Dos Drive" Press ESC to return to FDISK options

Enter #4 to "Delete Non-DOS Partition". Select the Non-DOS partition by typing the number and then ENTER. Press ESC to return to FDISK options. Note you cannot delete a NON-DOS partition located inside an Extended partition. You can use the DOS utility called delpart.exe from a DOS boot up.

Reboot with startup disk and load FDISK.

Say yes to Large disk support as above.

Enter choice #1 Press ESC to return to FDISK options

When asked if you want to use the maximum size for the partition and make it active, type Y if you want to use the whole drive, or N if you want to set a maximum sized for the partition.

After setting the size, reboot.

If you want to install another OS; after reboot: Type format X: at the A: prompt; where X is the drive/partition letter designation.

If you want to reinstall XP clean. After setting the size, reboot, remove the disk from the floppy drive and insert the XP CD in the CD drive.

Boot from the XP CD and do a clean install to the new partition.


Source of Information


You cannot format NTFS using a DOS boot disc, only FAT, use a XP installation CD as suggested earlier to format NTFS.


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Rather than DOS, you could boot to the Windows Recovery Console and use the commands available there. You can find this on your Windows install disc. HELP will show a list of commands.

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Use gparted instead. You simply burn a CD or create a USB stick, and you can perform all manner of operations on your disk partitions, including formatting, resizing, creating, and others. It's very handy.

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+1 Also PartitionMagic (for DOS) if you have it. – Synetech Sep 1 '12 at 22:24

dos dosen't have native NTFS support - there IS a driver that might be usable that avira used to have called ntfs4dos, but its no longer supported. Installing that MIGHT make the drive usable. You're better off, frustrationwise using a minimalist linux live cd and its copy of fdisk and mkdosfs to do the job tho

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ntfs4dos is something i've used, i remember using it in 2006, maybe it was around earlier perhaps before avira was out there. maybe avira bought it.. there is also NTFSPRO from sysinternals. As you suggest, I think it just provides read/write access, it doesn't add any new commands, so FORMAT would still only do FAT16 or FAT32 not NTFS. – barlop Oct 18 '11 at 13:23

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