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I have been reading about alternate data streams and I am kind of curious if any big applications for Windows actually uses this feature of NTFS.

I am also really curious as to whether or not traditional backup and archiving utilities back up this data and is able to be restored.

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As long as it is backed up to a NTFS partition, if you back up to a fat partition data streams are lost. – Moab Sep 9 '10 at 16:22
Most archiving utilities will not capture alternate streams. In fact, RAR/WinRAR is the only one I can think of off the top of my head (with the -os switch). – afrazier Sep 9 '10 at 17:08
Any backup application worth salt understands alternate data streams. You used to have to use an undocumented API to list them, but now with the FindFirstStreamW API there's no excuse. And they have all kinds of cool uses (e.g. thumbnail views and zone identifiers). – snoone Sep 14 '10 at 17:48

1 Answer 1

up vote 2 down vote accepted

Alternate Data Streams in NTFS Applies to

* Microsoft Win32 Application Programming Interface, when used with:
      o Microsoft Windows NT Advanced Server 3.1
      o Microsoft Windows NT 4.0
      o Microsoft Windows NT 3.51 Service Pack 5
      o Microsoft Windows NT 4.0
      o Microsoft Windows 2000 Standard Edition
      o the operating system: Microsoft Windows XP

Very small ADS (Alternate Data Streams) are also added within Internet Explorer (and now also other browsers) to mark files that have been downloaded from external sites: *they may be unsafe to run locally and the local shell will require confirmation from the user before opening them. When the user indicates that he no longer wants this confirmation dialog, this ADS is simply dropped from the MFT entry for downloaded files.

Resource from Wikipedia

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