Windows File and Folder “Attributes” A or C

Question

In Windows Server 2003, in the "Attributes" column of windows explorer, some files have "A" or "C" or "AC" or others. What do these mean?

Answer 1

The others are:

R = READONLY
H = HIDDEN
S = SYSTEM
A = ARCHIVE 
C = COMPRESSED
N = NOT INDEXED
L = Reparse Points
O = OFFLINE
P = Sparse File
I = Not content indexed
T = TEMPORARY
E = ENCRYPTED

I don't think I've ever seen the last two, but I do have files on my system that have the "N" designator which I don't recall ever seeing before Vista.

Answer 2

A = archive bit is set
C = compressed

Answer 3

Another attribute is E for Encrypted.

Answer 4

When Windows 7 "Backup and Restore" creates a "system image," it puts it in a root-level folder named WindowsImageBackup, which has the "I" attribute. Windows 7's "help attrib" command says:

C:\>help attrib
Displays or changes file attributes.

ATTRIB [+R | -R] [+A | -A ] [+S | -S] [+H | -H] [+I | -I]
       [drive:][path][filename] [/S [/D] [/L]]

  +   Sets an attribute.
  -   Clears an attribute.
  R   Read-only file attribute.
  A   Archive file attribute.
  S   System file attribute.
  H   Hidden file attribute.
  I   Not content indexed file attribute.
  [drive:][path][filename]
      Specifies a file or files for attrib to process.
  /S  Processes matching files in the current folder
      and all subfolders.
  /D  Processes folders as well.
  /L  Work on the attributes of the Symbolic Link versus
      the target of the Symbolic Link

Answer 5

You can do more with Attributes.

CMD-RUN-Type (Hidden Command)

Attrib +h +s C:\Test\Testing

CMD-RUN-Type (Show Command)

Attrib -h -s C:\Test\Testing

Enjoy..

Answer 6

Others are as follows;

H = Hidden

S = System File

R = Read Only

AHS and R can be set by the user or system, as user you can use the 'attrib' command to add/remove attributes. C is a system only attribute.

To find out more about the attrib command goto a command window and type 'attrib /?'

Answer 7

Backup software can clear the archive bit which is set when a file is modified. That way, it can be used to do incremental backups in order to skip over files that have already been backed up.

Since it can be set and unset at will, it's not necessarily the most reliable method and I think most backup software uses more sophisticated criteria for determining what to include in an incremental backup.

Answer 8

The A bit only shows up when you have backup software that sets it to indicate that file has been archived. When a user makes changes to a file, the operating system clears the archive bit, to indicate to the backup software that if it's doing an incremental or differential backup, it needs to backup that changed file and reset the A bit. Incremental backups reset the archive bit, so that the next incremental will only backup newly changed files. Differential backups do NOT reset the archive bit, so every differential backup grabs all the files that have changed since the previous full backup. So, to restore a system on Friday, an administrator would need the weekly backup from sunday and either the latest differential, or ALL the daily incrementals.

Answer 9

I am looking at several subdirectories on a shared network drive that have an "I" attribute, and one shortcut to a subdirectory that also has an "L" ("HSDLI"). I am going to guess the "I" could mean Indexed, but I haven't a clue to what "L" might mean. I would guess it means Link, but looking at other shortcuts to individual files at least, they don't have that attribute letter, so that is probably not it.