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Article ID: 104169 - Last Review: December 3, 2007 - Revision: 7.6

This article was previously published under Q104169

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The Backup program (Ntbackup.exe) automatically skips the following types of files during the backup and restore processes:
  • Files that are locked by a program other than Backup
  • Files that are skipped by default by Backup
  • By default, the Backup program that is included in Windows XP and in Windows Server 2003 uses a point-in-time shadow copy method to create backups of files that are locked by other programs. The information in this article applies only if Backup cannot do a volume shadow copy backup or if you select the Disable volume shadow copy option in the Advanced dialog box for an individual backup job. When this option is selected, some files that are open or that are being used during the backup may be skipped. We recommend that you do not select this option. (Do not disable this feature.) If Backup cannot do a volume shadow copy backup, Backup reverts to the pre-Windows XP backup method. The Disable volume shadow copy option is no longer available in Windows Server 2003 Service Pack 1 (SP1) and in later versions. Additionally, the SNAP command-line option is ignored in Windows Server 2003 SP1 and in later versions.
  • By default, the Backup utility is not installed by Windows XP Home Edition Setup. For additional information about how to install Backup, which is included on the CD-ROM in the Valueadd folder of the Windows XP Home Edition CD-ROM, click the following article number to view the article in the Microsoft Knowledge Base:
    302894  ( ) HOW TO: Install Backup from the CD-ROM in Windows XP Home Edition
  • The Windows NT version of the Backup program is called NTBackup.


Files That Are Locked by an Application Other Than Backup

Windows supports the backup of local files that are exclusively locked by the operating system, such as event logs and registry files; however, another type of skipped file that Backup encounters is a file that is in use and locked by another process.

In this kind of event, Backup displays a "Skip Open Files Wait Time" dialog box. An internal timer is then started and Backup waits 30 seconds for the file to become available. During that time, Backup continuously tries to access the locked file. If the file does not become available during the 30-second waiting period, Backup skips the file, places its name in the backup log file (if the log is enabled), marks it as skipped in the log, and continues to the next file. You have the option to choose the Cancel button in the dialog box and immediately move to the next file, logging the skipped file as previously described. If the file becomes available before the 30-second time-out period, Backup backs up that file and continues with the rest of the backup.

If the file has an attached alternate data stream that is locked, Backup waits 30 seconds for the stream to become available. If the stream does not become available in that time, Backup makes an entry in the log (if enabled) that indicates that the file was corrupted.

You can modify the following registry entries to adjust the skipped files options.Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756  ( ) How to back up and restore the registry in Windows
NOTE: In the U.S. version of Windows NT version 3.1 Service Packs 2 (and later), NTBackup does not use the registry, but instead uses %SYSTEMROOT%\Ntbackup.ini.

HKEY_CURRENT_USER\Software\Microsoft\Ntbackup\User Interface
   Name:            Skip open files
   Type:            REG_SZ
   Default:         0
   0 = do not skip, wait
   1 = skip files that are opened unreadable
   2 = wait on open files for "Wait time"
   Name:            Wait time
   Type:            REG_SZ
   Data:            30
   Maximum time (seconds) to wait for open files. Default is 30 seconds.
   Maximum value is 65535

Files That Are Skipped by Default by Backup

By default, Backup skips the following files:
  • Files that you do not have permission to read. Only those users with backup rights can copy files that they do not own in Backup. To copy files that you do not own in Windows 2003 or later, you must be a member of the Administrators or Backup Operators group on the local computer, or you must have been delegated the appropriate authority.
  • Files that are temporary in nature. These files are neither backed up nor restored by Backup. Examples include Pagefile.sys, Win386.swp, 386spart.par, Backup.log, and Restore.log. The list of skipped files is hard-coded into Backup and cannot be changed.
  • Registry files on remote computers. Windows backs up only local registry files.
For Windows 2000, the Backup##.log files for the "active" backup_user are not backed up in the following folder:
Documents and Settings\User_name\Local Settings\Application Data\Microsoft\Windows NT\NTbackup\Data

Files that are skipped by default by Backup in Windows Server 2003

The following files are not backed up by Backup in Windows Server 2003:
  • The backup file that is created by the active backup job cannot be backed up. For example, if you name the backup file "Backup.bkf," this file is in use during the backup process and cannot be backed up.
  • Pagefile.sys
  • Ea data.sf
  • $RestoredActiveFile*
  • Data*.log (contained in the Documents and Settings\User\Local Settings\Application Data\Microsoft\Windows NT\NTBackup\Data folder).
  • Files that are created by Backup in the following folder:
    Documents and Settings\All Users\Application Data\Microsoft\Windows NT\NTBackup\Catalogs51
  • Ntdll.dll
  • Smss.exe

  • Microsoft Windows Server 2003, Standard Edition (32-bit x86)
  • Microsoft Windows Server 2003, Enterprise Edition (32-bit x86)
  • Microsoft Windows Server 2003, Datacenter Edition (32-bit x86)
  • Microsoft Windows XP Professional x64 Edition
  • Microsoft Windows XP Home Edition
  • Microsoft Windows XP Professional
  • Microsoft Windows XP Media Center Edition
  • Microsoft Windows XP Tablet PC Edition
  • Microsoft Windows 2000 Server
  • Microsoft Windows 2000 Advanced Server
  • Microsoft Windows 2000 Professional Edition
  • Microsoft Windows NT Server 4.0 Standard Edition
  • Microsoft Windows NT Workstation 4.0 Developer Edition
  • Microsoft Windows NT Server 3.51
  • Microsoft Windows NT Workstation 3.51
  • Microsoft Windows NT Server 3.5
  • Microsoft Windows NT Workstation 3.5
  • Microsoft Windows NT Advanced Server 3.1
  • Microsoft Windows NT Workstation 3.1
  • Microsoft Windows Small Business Server 2003 Premium Edition
  • Microsoft Windows Small Business Server 2003 Standard Edition
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