A utility aimed at overcoming some of the problems created by
the 'junctions' in Windows Vista/7
user-profiles.
An issue experienced by users of Windows Vista or Windows 7 is that the
user-profiles (Which are now stored under "Users" instead of "Documents
and Settings") cannot be copied, transferred or backed-up in any simple
way. This is owing-to the presence of 'junctions' within the
profile. JunctionBox offers a solution to this problem, by making
it possible to backup and restore the junctions from a catalog. This
catalog is a standard text file which can be backed-up in the
normal way.
-What is a junction?
A junction is a filesystem object not unlike a folder/directory (in
fact it appears to most software that it IS a folder) but which is in
reality a link to a folder elsewhere on the disk, or even on another disk.
When used carefully, junctions allow data from other sources to be
included-into a folder-structure, such that software need not even be
aware that the data is in fact located elsewhere. This can be useful in
a number of circumstances.
-Why are Vista/7's junctions problematic, then?
Vista/7 user-profiles follow a different structure from those in
Windows 2000/XP. To allow older software to function correctly in
Vista/7, junctions are used to simulate the presence of the oldstyle
profile-folders.
The key issue here is that some of these junctions are cyclic, that is
they refer back to their own folder-structure, rather like a snake
eating its own tail. The result is that programs which scan the
folder-structure get stuck in an endless loop when they hit these
cyclic junctions.
In an attempt to 'fix' this, Microsoft gave the junctions a special
permission, that of Deny List Contents to Everyone. The idea here is
that software which tries to scan the structure should see the
junctions as being empty folders, and ignore them. Unfortunately the
fix doesn't always work. This is primarily because backup-programs
often have special rights to bypass restrictions on folders, thus the
Deny permission is in this case not effective in preventing an endless
loop.
Add to that, most file-copy routines simply don't know what to do with
junctions (and this even includes Microsoft's own utilities!) thus a
backup of a user's profile may omit the junctions entirely.
-What does Junction Box do?
JunctionBox allows you to backup and restore junctions to or from a
catalog-file. It also allows you to delete them, if this is found
necessary so that a backup of the profile proceeds normally.
Creating a Backup:
Press Backup, and enter a suitable filename and location. Or just
accept the suggested name. (The suggested extension is .ntj) By
default, backups are saved to the program's own folder, since this is
intended to be a portable utility. Depending on the amount of data on
your disk, this may take a minute, or an hour. Once finished you should
have a backup file. The structure of this is explained in
DefaultJunctions.ntj
Backups always include the full set of junctions, the profile selector having no effect on this function.
Restoring Junctions:
Firstly select whether you wish to restore the set of junctions for the
system-disk, or just those in a specific user-profile.
You will then be presented with a file selector, from which the appropriate catalog should be selected.
A set of standard junctions is provided is the file
DefaultJunctions.ntj, and this may be useful where you need to repair a
computer for which no catalog has been made.
The restore process is relatively quick as only a small amount of data need be scanned, just the junctions.
After being restored, the junctions will have their special permissions
applied, so that (well, in the hope that) this will prevent endless
loops.
At present the software does not provide any way of restoring junctions
without also adding these special permissions. If thought necessary
this facility could be added.
Deleting Junctions:
Select the profile to delete the junctions within, and select Delete
from the Junctions menu. Again you will be asked to specify a catalog
file. This is NOT so that a backup can be made, and the catalog will
not be altered. What happens here is that the catalog is used to
identify the junctions to delete.
This approach is seen as being relatively safe, in that junctions will
only be deleted which have already been included in the catalog. So, if
you didn't backup, then you can only delete the default set of
junctions, using DefaultJunctions.ntj. If you want to delete custom
junctions which you've added yourself, then you need to backup first.
Which, I think, makes sense.
Dependencies:
JunctionBox requires SetACL.exe by Helge Klein. This is included in the
distribution, and is GPL licensed. The sourcecode is available from
setacl.sourceforge.net.
The MKLINK component of cmd.exe is also required for restore
operations, which rules-out use on platforms earlier than Vista. That
said, earlier platforms such as Windows XP do not normally require a
junction manager.
Notes:
Never attempt to delete a junction using Windows Explorer. You will
probably not succeed, but if you DO, this will result in the contents
being deleted instead of the junction itself, which could potentially
be a disaster.
International Versions of Windows:
The names of system folders differ between languages, therefore a
catalog made in one language should not be applied to another. To
reduce the risk of accidents of this kind, the catalog-file header
carries the locale information. You can edit this manually if you are
sure that the file is suitable for your locale. See the comments in
DefaultJunctions.ntj for more information.
Presently there is no support for languages which use special
character-sets, which includes most Asian languages. As I don't have
access to a suitable platform to test such aspects on, feedback or
suggestions from users who do would be welcome. Be aware that operation
on these language-versions is completely unverified, so please don't do
your tests on a production computer!
Making your own DefaultJunctions file:
To make a DefaultJunctions.ntj file, run the backup option on an
unmodified copy of the required Windows localization. Edit the file
this produces using a text-editor (e.g. Notepad) to remove the
useraccount-specific sections. Retain the system-folder sections and
the All Users, Public and Default (or language equivalent thereof)
profile sections. If necessary, add any more applicable locales to the
OSLanguanges value in the General section, separated by commas. Now
rename the file to DefaultJunctions.ntj
As ever, you use this system-level utility entirely at your own risk.
Various forms of disaster are not excluded from the list of possible
outcomes of its incorrect use. Or, even of its correct use.
This software may be duplicated any number of times, and used in
private or commercial IT operations. The software may not be sold for
profit in any shape or form. Third-party websites and P2P hosts may
offer copies for download so long as these conditions are met.
The sourcecode and executables of this software are released under the
GNU Public Licence, version 3. Icons and other graphics remain the
intellectual property of IWR Consultancy, and may not be used in
derivative works without permission.
It is not necessary to supply sourcecode with every downloaded copy, so
long as a link to the publisher's website is included in some form or
other at the download location.
The author supports the principle of the complete abolition of patents,
and the review of copyright legislation to reduce its present levels of
abuse.
