just another useful tool

Discussion in 'other software & services' started by clansman77, Mar 7, 2005.

Thread Status:
Not open for further replies.
  1. clansman77

    clansman77 Registered Member

    Jan 31, 2005

    Look for the latest version here:


    With the invention of Windows 95 Microsoft made the wise decision to
    organize all computer- and application-specific data which was spread
    over countless INI files before in a centralized Windows database,
    called the system "registry". The registry is one of the most
    important parts in every Windows system today, without which the OS
    would not even boot. And since the registry is quite sensitive to
    corruption, it is very advisable to backup its according files from
    time to time.

    In MS-DOS based Windows versions (95, 98, Me) the registry consists of
    the files SYSTEM.DAT and USER.DAT (and CLASSES.DAT in Windows Me). To
    backup these files, one can easily go to the Windows folder in
    Explorer and copy the files to a safe location, for example another
    folder on the hard disk. Microsoft even supplies a utility called ERU
    which can be used to backup these and a few other critical system
    files to a safe location.

    Also, Windows 9x/Me automatically create backups of the registry at
    startup, with Windows 95 always backing up the registry from the
    previous Windows session, and Windows 98/Me maintaining up to five
    registry copies from the last five days where Windows was running.

    Unfortunately, this is not the case with Windows versions based on the
    NT kernel. In Windows NT and 2000, the registry is never backed up
    automatically, and in XP it is backed up only as part of the bloated
    and resource hogging System Restore program which cannot even be used
    for a "restore" should a corrupted registry prevent Windows from
    booting. It has also become impossible to copy the necessary files,
    now called "hives" and usually named DEFAULT, SAM, SECURITY, SOFTWARE,
    SYSTEM in the SYSTEM32\CONFIG folder, to another location because they
    are all in use by the OS. And though the registry in an NT-based
    Windows is less likely to become corrupted than in other versions, it
    can still happen, and for these cases NT is simply missing an option
    for easy registry backup and restore as there is in Windows 9x/Me, to
    get the system up and running again in no time.

    In 2001, as Windows XP began to come pre-installed on many new home
    user PCs and was likely to become the new Windows standard over the
    next years, I decided to write a program which offers the ease-of-use
    of Windows 9x/Me ERU by Microsoft (hence the name ERUNT) to backup the
    registry, as well as providing an auto-backup capability, for example
    at Windows startup.

    Or, before installing a new program for testing purposes one could
    save the registry with ERUNT, install and test the program, uninstall
    it and restore the registry to be 100% sure that no debris is left.

    Note: The "Export registry" function in Regedit is USELESS (!) for
    making a complete backup of the registry. Neither does it export the
    whole registry (for example, no information from the "SECURITY" hive
    is saved), nor can the exported file be used later to replace the
    current registry with the old one. Instead, if you re-import the file,
    it is merged with the current registry without deleting anything that
    has been added since the export, leaving you with an absolute mess of
    old and new entries.


    - Backup the Windows NT/2000/2003/XP registry to a folder of your

    - System and current user registries selectable

    - Command line switches for automated registry backup and restoration

    - Restore the registry in Windows 9x/Me/NT/2000/2003/XP and MS-DOS
    (all-in-one restore program) or the Windows Recovery Console

    - Included in this package:
    NTREGOPT program for optimizing the registry

    - All programs in this package are completely localizable
    (translate them into your language), German version included

    Supported operating systems

    - Windows NT 3.51
    - Windows NT 4.0
    - Windows 2000
    - Windows 2003
    - Windows XP
    - most likely, all future Windows versions based on the NT kernel

    Additionally supported by the ERDNT restore program:
    - MS-DOS
    - Windows 95
    - Windows 98
    - Windows Me

    Restoring the registry with ERDNT

    Situation: Windows is running normally.

    To restore a previous registry backup, open Windows Explorer, navigate
    to the folder where you saved the backup to, and double-click the
    ERDNT.EXE file to start the restoration program. (Each restore folder
    has its own copy of ERDNT.EXE in it.) Select which registry components
    to restore, then click "OK" to start restoration. When the process is
    complete, click "OK" to restart the computer and activate the restored

    Note: If you experience any problems restoring the registry, please
    read "ERDNT technical information" later in this document to learn
    what ERDNT is actually doing during the process, or simply read on
    through the following emergency scenarios for other ways of restoring
    the registry.

    What to do if Windows does not boot anymore?

    If Windows refuses to boot normally it can be for a variety of
    reasons, not the least of which is that the registry is damaged, or
    you installed a program or driver which is somewhat incompatible with
    the system or buggy, in which case restoring a registry backup from a
    point where everything was running smoothly should also help.

    The first thing to try is to reboot and press the F8 key immediately
    before the first Windows screen appears, then select the "Last Known
    Good" option from the menu and see if Windows boots up with this
    option. If it does, you're all set.

    If it does not, reboot again with F8, and select the option "Safe
    Mode". If Windows boots up in safe mode, you can restore a registry
    backup just as you would in normal mode, as described above.

    If safe mode also fails, read on...

    Restoring the registry with ERDNT - Emergency Scenario I

    Situation: Windows fails to boot up in normal and safe mode, but you
    have a DOS boot disk or another (working) operating system installed
    on your PC which is supported by the ERDNT restoration program, and
    from which you have full access to the drive(s) containing the corrupt
    Windows installation and the registry backup.

    Boot up to the working OS, and open the folder containing the registry
    backup you want to restore.

    If the drive letters are different to as they were in the Windows
    where you created the registry backup, you need to edit the ERDNT.INF
    file now to reflect the new drive letters, before trying to restore
    the registry backup. For example, if the drive with the corrupt
    Windows installation is now available as D: instead of C:, then you
    would change all C:\... references in the INF file to D:\... . Editing
    the file can be done in Windows with the Notepad program, and in DOS
    with the EDIT command.

    Now run the ERDNT.EXE file to start the restoration program. Select
    which registry components to restore (just the system registry will do
    in most cases), then start restoration. When the process is complete,
    reboot the computer and check if the other Windows installation is
    repaired now.

    Restoring the registry with ERDNT - Emergency Scenario II

    Situation: Windows fails to boot up in normal and safe mode, and you
    have no other working operating system installed on your PC.

    The following two rescue methods require that your PC is configured so
    that it can boot from CD. See your BIOS documentation for more

    1. Bart's PE Builder
    Use another computer with Internet access and CD burning capabilities
    to download this free program from the Internet (do a Google search
    for it), which will create a bootable Windows CD with full access to
    all drives (including NTFS). Boot from this CD, open the File
    Management Utility and follow the directions in "Emergency Scenario I"
    to run ERDNT and restore the registry.

    2. The Windows Recovery Console (Windows 2000 and higher)
    Note that you can use this method only if you saved the registry
    backup inside the Windows folder, and that using this procedure only
    the system registry is restored. This should however get you back into
    Windows, from where you can run the ERDNT program to restore user
    registries, if necessary.
    - Boot your system from the Windows 2000/2003/XP CD-ROM.
    - At the welcome screen, press "R" (Windows 2000: "R" then "C").
    - Type in the number of the Windows installation you want to repair
    (usually 1), then press ENTER.
    - Type in the Administrator password and press ENTER.
    - At the command prompt type
    cd erdnt
    or whatever you named your restore folder, then press ENTER.
    - If you created subfolders for different registry backups (for
    example, with the different creation dates), type
    dir <ENTER>
    to see a list of available folders, then type
    cd foldername <ENTER>
    where foldername is the name of a folder listed by the dir command,
    to open that folder.
    - Now type
    batch erdnt.con <ENTER>
    to restore the system registry from that folder.
    - Type
    exit <ENTER>
    and remove the CD from the CD-ROM drive. The system will now reboot
    with the restored registry.
  2. Clowny

    Clowny Registered Member

    Aug 11, 2004
    Good stuff. :) I've been using ERUNT and NTREGOPT for a while with good results.
  3. clansman77

    clansman77 Registered Member

    Jan 31, 2005
    indeed its a very useful tool.unlike other registry backups softwares this one is a gem.. :cool: and you never know when the autoregistry backup at startup will come handy..
  4. clansman77

    clansman77 Registered Member

    Jan 31, 2005
Thread Status:
Not open for further replies.
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.