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Topic: Defragmented file prefixed $
I have just defragmented my hard drive (I use O&O defrag) and there is a
badly defragmented but locked file C:\$extend\$UsnJrnl:$J$DATA. What is the
significance of this file and the $ prefix? Can I delete it? Thanks.
Replies below ↓
Replies
Re: Defragmented file prefixed $
> What is the significance of this file and the $ prefix?
Files with a dollar sign prefix ($) are usually hidden from the Windows API
(Application Programming Interface). Like the Master File Table ($mft).
> Can I delete it?
I would not. Maybe someone that knows more than I do will advise
differently.
[[NTFS includes several system files, all of which are hidden from view on
the NTFS volume. A system file is one used by the file system to store its
metadata and to implement the file system. System files are placed on the
volume by the Format utility.
$Extend is an NTFS system file. Used for various optional extensions such
as quotas, reparse point data and object identifiers.]]
from...
NTFS System Files
http://www.ntfs.com/ntfs-system-files.htm
[[Not all NTFS volumes contain a $UsnJrnl file. A $UsnJrnl file is created
on a volume only when a program that uses the file makes the first write
request.]]
from..
Error messages when you try to gain access to an NTFS volume
http://support.microsoft.com/kb/311724
$UsnJrnl
[[Update sequence number (USN) change journal, which provides a persistent
log of all changes made to files on the volume. As files, directories, and
other NTFS objects are added, deleted, and modified, NTFS enters records
into the USN change journal, one for each volume on the computer. Each
record indicates the type of change and the object changed.
Programs can consult the USN change journal to determine all the
modifications made to a set of files. The USN change journal is much more
efficient than checking time stamps or registering for file notifications.
The USN change journal is enabled and used by the Indexing Service, File
Replication Service (FRS), Remote Installation Service (RIS), and Remote
Storage.]]
from...
ntcmds.chm::/fsutil_usn.htm
What is $Usnjrnl?
[[The Windows 2000 Change Journal is a database that contains a list of
every change made to the files or directories on an NTFS 5.0 volume. Each
volume has its own Change Journal database that contains records reflecting
the changes occurring to that volume's files and directories.]]
Keeping an Eye on Your NTFS Drives: the Windows 2000 Change Journal
Explained
http://www.microsoft.com/msj/0999/journal/journal.aspx
SWAG: You have the Indexing Service running or had it running and it created
C:\$extend\$UsnJrnl:$J$DATA.
--
Hope this helps. Let us know.
Wes
MS-MVP Windows Shell/User
In news:F0AA1995-6F6A-4937-8C47-1BF03E658189@microsoft.com,
billzxgolf <billzxgolf@discussions.microsoft.com> hunted and pecked:
> I have just defragmented my hard drive (I use O&O defrag) and there is a
> badly defragmented but locked file C:\$extend\$UsnJrnl:$J$DATA. What is
> the significance of this file and the $ prefix? Can I delete it? Thanks.
Re: Defragmented file prefixed $
"billzxgolf" wrote
>I have just defragmented my hard drive (I use O&O defrag) and there is a
> badly defragmented but locked file C:\$extend\$UsnJrnl:$J$DATA. What is
> the
> significance of this file and the $ prefix? Can I delete it? Thanks.
Why would you want to? It almost certainly isn't causing any problems.
It's a system file. Don't mess with them. If you are that obsessed with
defragmenting this file try Raxco's Perfect Disk. It can defrag locked
system files and meta data during an offline defrag, but I wouldn't worry
about it.
--
Rock [MVP - User/Shell]
Re: Defragmented file prefixed $
"Rock" wrote:
> "billzxgolf" wrote
>
> >I have just defragmented my hard drive (I use O&O defrag) and there is a
> > badly defragmented but locked file C:\$extend\$UsnJrnl:$J$DATA. What is
> > the
> > significance of this file and the $ prefix? Can I delete it? Thanks.
>
> Why would you want to? It almost certainly isn't causing any problems.
> It's a system file. Don't mess with them. If you are that obsessed with
> defragmenting this file try Raxco's Perfect Disk. It can defrag locked
> system files and meta data during an offline defrag, but I wouldn't worry
> about it.
>
> --
> Rock [MVP - User/Shell]
>
> Thanks for the info. The only reason I want to defragment it is because it is in about 40 fragments all through my free disk space, which means that I could get problems with future programme installations that require large chunks of contiguous disk space.
Re: Defragmented file prefixed $
"Wesley Vogel" wrote:
> > What is the significance of this file and the $ prefix?
>
> Files with a dollar sign prefix ($) are usually hidden from the Windows API
> (Application Programming Interface). Like the Master File Table ($mft).
>
> > Can I delete it?
>
> I would not. Maybe someone that knows more than I do will advise
> differently.
>
> [[NTFS includes several system files, all of which are hidden from view on
> the NTFS volume. A system file is one used by the file system to store its
> metadata and to implement the file system. System files are placed on the
> volume by the Format utility.
>
> $Extend is an NTFS system file. Used for various optional extensions such
> as quotas, reparse point data and object identifiers.]]
> from...
> NTFS System Files
> http://www.ntfs.com/ntfs-system-files.htm
>
> [[Not all NTFS volumes contain a $UsnJrnl file. A $UsnJrnl file is created
> on a volume only when a program that uses the file makes the first write
> request.]]
> from..
> Error messages when you try to gain access to an NTFS volume
> http://support.microsoft.com/kb/311724
>
> $UsnJrnl
> [[Update sequence number (USN) change journal, which provides a persistent
> log of all changes made to files on the volume. As files, directories, and
> other NTFS objects are added, deleted, and modified, NTFS enters records
> into the USN change journal, one for each volume on the computer. Each
> record indicates the type of change and the object changed.
>
> Programs can consult the USN change journal to determine all the
> modifications made to a set of files. The USN change journal is much more
> efficient than checking time stamps or registering for file notifications.
> The USN change journal is enabled and used by the Indexing Service, File
> Replication Service (FRS), Remote Installation Service (RIS), and Remote
> Storage.]]
> from...
> ntcmds.chm::/fsutil_usn.htm
>
> What is $Usnjrnl?
> [[The Windows 2000 Change Journal is a database that contains a list of
> every change made to the files or directories on an NTFS 5.0 volume. Each
> volume has its own Change Journal database that contains records reflecting
> the changes occurring to that volume's files and directories.]]
> Keeping an Eye on Your NTFS Drives: the Windows 2000 Change Journal
> Explained
> http://www.microsoft.com/msj/0999/journal/journal.aspx
>
> SWAG: You have the Indexing Service running or had it running and it created
> C:\$extend\$UsnJrnl:$J$DATA.
>
> --
> Hope this helps. Let us know.
>
> Wes
> MS-MVP Windows Shell/User
>
> In news:F0AA1995-6F6A-4937-8C47-1BF03E658189@microsoft.com,
> billzxgolf <billzxgolf@discussions.microsoft.com> hunted and pecked:
> > I have just defragmented my hard drive (I use O&O defrag) and there is a
> > badly defragmented but locked file C:\$extend\$UsnJrnl:$J$DATA. What is
> > the significance of this file and the $ prefix? Can I delete it? Thanks.
>
> Thanks for the reply, it helped a lot.