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Using the command line tool cipher.exe built into Windows 7, can it be used to securely wipe a USB attached drive?

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migrated from Jan 14 '11 at 1:17

This question came from our site for system and network administrators.

Try sdelete instead? – Zoredache Jan 14 '11 at 1:11
up vote 5 down vote accepted

Yes, but it may be slow compared to other tools that do the same job.

cipher /w:X

Substitute the drive letter X for your flash drive.

Remember this only overwrites free space, so delete all files first.

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Most free-space wipe tools I've seen, including sdelete and cipher /w work the same way: they create a really big file and fill it with random data (which they most likely obtain using CryptGenRandom). I don't see why would cipher be slower than others. – grawity Jan 14 '11 at 12:31
@ grawity, I did use the word "may" – Moab Jan 14 '11 at 15:31
cipher /w:X: with double point at the end for drive X! – user185570 Jan 9 '13 at 6:58

You can also use sdelete from

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Just commenting the answer given already (comments cannot be styled).

This is part of help printout for cipher.exe

Displays or alters the encryption of directories [files] on NTFS partitions.

  CIPHER /W:directory

   /W        Removes data from available unused disk space on the entire
              volume. If this option is chosen, all other options are ignored.
              The directory specified can be anywhere in a local volume. If it
              is a mount point or points to a directory in another volume, the
              data on that volume will be removed.

Is this true that only NTFS file system can be "cipher-ed"?

What about FAT32 format which is used lately for UEFI compatibility?

Seems better to use special utilities for wiping.

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