This tip describes how to move an installation of Windows XP to new, upgraded, or just different hardware. By using this information, you can:
- Migrate a working Windows XP operating system and your installed programs to a different or more powerful computer in minimal downtime.
- Replace a small system/boot disk drive with a larger system/boot disk drive.
- Restore a Windows backup from a malfunctioning computer to a different computer for disaster recovery purposes.
Windows Backup (Ntbackup.exe) can handle differences in hardware configuration information between computers and maintain critical registry entries that are unique to the computer to which you are migrating information. This capability means that you can
migrate to new hardware by performing a full backup of the source computer and then restoring the backup over a fresh installation of Windows XP on the destination computer.
Ntbackup.exe handles restore operations in the registry by first querying the following registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\BackupRestore\KeysNotToRestoreThis registry key indicates to Ntbackup.exe that certain registry keys under the HKEY_LOCAL_MACHINE\SYSTEM key should not be overwritten when files are restored.
An entry that ends with a backslash (\) indicates that a key is protected and that any keys or values under that key should not be restored. If the entry ends with a backslash and an asterisk (\*), all subkeys are "merged." In this situation, "merged" means comparing the start values of the keys in the backup set with the start values that exist in the current registry, to determine the correct key to restore.
If the value of the key on the backup set has a lower start value, the backup key takes precedence. If the value of the key in the current registry has a lower start value, the current key takes precedence. This process ensures that all services and devices start correctly after a "system state" restoration, even on dissimilar hardware.
For example: If the value of the following key on the backup set has a lower start value, the backup key takes precedence:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\DhcpIf the value of the same key in the current registry has a lower start value than the key you want to restore, the current key takes precedence.
Original System New System: Before Restore After Restore ======================================================================== DHCP Running: YES NO YES DHCP Running: NO YES YES DHCP Running: NO NO NOAfter the computer successfully restarts, Windows Plug and Play takes care of any minor differences in hardware configuration.
Drive Letters and the %SystemRoot% FolderFor a complete migration to work correctly, the %SystemRoot% folder (the Windows folder in Windows XP) and the drive letters for any (target) volumes that contain a system-state component must be the same on both the source computer and the destination computer. This means that if the source computer has, for example, Windows XP Professional installed in the C:\Windows folder and has Active Directory (NTDS) and SYSVOL on separate drives, drive D and drive E respectively, the destination computer must have Windows XP pre-installed in a C:\Windows folder and contain drives D and E before the restore operation can succeed.
Hardware Abstraction Layer (HAL)The HALs on both of the computers should be the same. This means that the source and destination computers should be using the same HAL type to achieve favorable results. Although this is not a requirement, the computer may not perform migration properly if the HALs do not match.
To determine the type of HAL that you are using on each computer:
- Click Start , click Control Panel , and then double-click System .
- On the Hardware tab, click Device Manager , and then view the listing under Computer . Possible values for the system description and the associated HAL include:
ACPI Multiprocessor PC = Halmacpi.dll
ACPI Uniprocessor PC = Halacpi.dll
Advanced Configuration and Power Interface (ACPI) PC = Halacpi.dll
MPS Multiprocessor PC = Halmps.dll
MPS Uniprocessor PC = Halapic.dll
Standard PC = Hal.dll
Compaq SystemPro Multiprocessor or 100% Compatible = Halsp.dll
The Windows\Repair FolderThe Windows\Repair folder that contains your source computer hardware and software configuration files and the Setup.log file may not be valid for the new hardware on the destination computer to which you restored them. You should perform an in-place upgrade on the destination computer to update these files so that you can make the appropriate repairs in the future if necessary.
NTFS VolumesYou may need to start special filter drivers before you can restore files that contain reparse points to NTFS volumes. This means that before you can restore these types of files, you need to restart the computer after you restore the operating system. Examples of these types of files include Remote Installation Services (RIS) images that rely on Single Instance Storage (SIS), Remote Storage Server (RSS) files that you are restoring to managed volumes, or other third-party services that use reparse points and require filter drivers.
The Procedure for Moving a Windows Installation
- On the destination computer, perform a new installation of Windows, using the product type that matches that of the source computer. Ensure that the drive letter and %SystemRoot% folder names match those on the source computer.
- Using Disk Management, create, format, and assign drive letters to any additional volumes that may be required to hold a system-state component (for example, SYSVOL, Active Directory, or Active Directory Log files). Ensure that all drive letters match those on the source computer.
- On the source computer, log on as Administrator, and then stop all the non-essential services that you normally stop before performing a backup.
- Using Ntbackup.exe, back up the system\boot volume, the system state, and associated NTDS and SYSVOL volumes, if applicable.
- On the destination computer, log on as Administrator. If the system that you want to restore is a destination computer, you must restart the computer, press F8 during startup, and then click Directory Services Restore Mode before you log on as Administrator.
- Start Ntbackup.exe, click Options on the Tools menu, click the Restore tab, and then click Always replace the file on my computer . Restore the system\boot volume, the system state, and associated volumes from the backup that you performed previously. Make sure that you select the option to restore them to "original location" in the backup program.
- After the full restoration finishes, and before you restart the destination computer, make sure that the computer is disconnected from the network, to avoid conflicts.
Restart the computer.
- If the computer does not restart after restoration because of HAL mismatches, you can start from the Windows installation disk to perform an in-place installation or repair. This type of repair occurs after you accept the licensing agreement, and Setup searches for previous versions to repair. When the installation that is damaged or needs repair is found, press R to repair the selected installation. Setup re-enumerates your computer's hardware (including the HAL) and performs an in-place upgrade while maintaining your programs and user settings. This also refreshes the %SystemRoot%\Repair folder with accurate information that you can use for normal repairs.
- If the computer does restart after the restoration, log on as Administrator and initiate an in-place upgrade by running Winnt32.exe from the i386 folder on the Windows CD-ROM. This refreshes the Setup.log and registry files in the %SystemRoot%\Repair folder, and ensures that the proper HAL is in use.
- After the upgrade is finished and you are certain that everything works, you can remove the source (original) computer from the network and connect the destination (new) computer in its place.
For additional information about drive letter assignments,, click the article number below to view the article in the Microsoft Knowledge Base:
Q307844 HOW TO: Change Drive Letter Assignments in Windows XP
For additional information about how to perform a backup, click the article number below to view the article in the Microsoft Knowledge Base:
Q308422 HOW TO: Use Backup to Back Up Files and Folders on Your Computer
For additional information about how to restore, click the article number below to view the article in the Microsoft Knowledge Base:
Q309340 HOW TO: Use Backup to Restore Files and Folders on Your ComputerNOTE : To have access to all removable media (tape or magneto-optic \[MO\] disk) from the source computer after the full system restore is complete, you must also click Restore Removable Storage Database under Advanced before you begin the restore.
For additional information about re-activation after the restore, click the article number below to view the article in the Microsoft Knowledge Base:
Q305356 Windows XP Prompts You to Re-activate After You Restore Your ComputerFor information about how to install Ntbackup on a computer that runs Windows XP Home Edition, see the following article in the Microsoft Knowledge Base:
Q302894 HOW TO: Install Backup from the Windows XP Home Edition CD-ROM