© J.C. Kessels 2009
Delete the Update Sequence Number (USN) change journal.
The journal is stored in a huge file called "$Extend\$UsnJrnl:$J:$DATA" in the
root of a volume, and is invisible to (most) applications.
MyDefrag on Windows 7 can move and defragment the journal, but not on older Windows
- The USN change journal is a database of all changes made to files on a volume.
Windows enters records into the journal when files, directories, and
other objects are added, deleted, and modified. Programs can consult the
journal to quickly determine all the modifications made to a set of files, much
more efficiently than checking time stamps or registering for file notifications.
- The journal is disabled by default, and automatically enabled and used by the
Indexing Service, File Replication Service (FRS), Remote Installation Service (RIS),
and Remote Storage. Third party programs can also use the USN change journal.
- After deleting the journal Windows will automatically create a new journal and
record volume changes from that moment on.
- Deleting the journal is usually safe, but can have consequences. Applications that
are using it will not see file changes between the last time the application ran and
when the journal was deleted. Well-programmed applications will detect that the
journal was deleted and will revert to an alternative method of finding changed
Note: For the File Replication Service see the "Enable Journal Wrap
Automatic Restore" registry setting.
- Deleting the journal may take a long time on a volume with many files.
- The journal is an NTFS facility. It does not exist on FAT disks or other
- The journal is a sparse file. The size that is reported by Windows includes
unused blocks, the actual space occupied on disk is listed by MyDefrag in the
- The journal can also be deleted from the Windows Run commandline with the
command, in Windows 2003/XP/Vista, not Windows 2000. The "fsutil" command must be
run as administrator and can take several minutes to finish.
Example of the commandline:
|fsutil usn deletejournal /n c:|
# Delete the USN change journal.
See also: VolumeActions