Windows Preinstallation Environment (AKA Windows PE and WinPE) is a lightweight version of Windows used for the deployment of PCs, workstations, and servers, or troubleshooting an operating system while it is offline. It is intended to replace MS-DOS boot disks and can be booted via USB flash drive, PXE, iPXE,CD-ROM, or hard disk. Traditionally used by large corporations and OEMs (to preinstall Windows client operating systems on PCs during manufacturing), it is now widely available free of charge via the Windows Automated Installation Kit (WAIK).
WinPE was originally intended to be used only as a pre-installation platform for deploying Microsoft Windows operating systems, specifically to replace DOS in this respect. WinPE has the following uses:
- Deployment of workstations and servers in large corporations as well as pre-installation by system builders of workstations and servers to be sold to end users.
- Recovery platform to run 32-bit or 64-bit recovery tools such as Winternals ERD Commander or the Windows Recovery Environment (Windows RE).
- Platform for running third-party 32-bit or 64-bit disk cloning utilities.
The package can be used for developer testing or as a recovery CD/DVD for system administrators. Many customized WinPE boot CDs packaged with third-party applications for different uses are now available from volunteers via the Internet.
The package can also be used as the base of a forensics investigation to either capture a disk image or run analysis tools without mounting any available disks and thus changing state.
Version 2.0 introduced a number of improvements and extended the availability of WinPE to all customers, not just corporate enterprise customers by downloading and installing Microsoft’s Windows Automated Installation Kit (WAIK).
It was originally designed and built by a small team of engineers in Microsoft’s Windows Deployment team, including Vijay Jayaseelan, Ryan Burkhardt, and Richard Bond.
The following versions are known to exist:
|1.0||The first release of Windows Preinstallation Environment|
|1.1||Built from Windows XP Professional with Service Pack 1|
|1.2||Built from Windows Server 2003 family|
|1.5||Called Windows PE 2004; built from Windows XP Professional with Service Pack 2|
|1.6||Called Windows PE 2005; built from Windows Server 2003 with Service Pack 1|
|2.0||Built from the first edition of Windows Vista. This version differs from the other versions since it doesn’t need the disc to load all the files. This means that the download is now 992 MB in size instead of 60 MB from the previous versions. It’s possible to modify the default startup disc to have access to a few plug-ins like Windows Management Instrumentation, Windows Scripting Host, additional drivers and other 32-bit applications (or 64-bit applications for 64-bit versions). Other new features include the capability for a rewritable RAM disk since WinPE version 1.x only has a recordable RAM disk.|
|2.1||Built from Windows Server 2008|
|2.2||Built from Windows Server 2008 SP2|
|3.0||Built from Windows 7 code base. It is included in WAIK 2.0.|
|3.1||Built from Windows 7 SP1 code base. It is included in Windows Automated Installation Kit (AIK) Supplement for Windows 7 SP1 available from Microsoft’s website.|
|4.0||Built from Windows 8 code base. It is included in Windows ADK (Windows Kits 8.0) and available from Microsoft’s website.|
|5.0||Built from Windows 8.1 code base. It is included in Windows ADK (Windows Kits 8.1) and available from Microsoft’s website.|
|5.1||Windows ADK (Windows Kits 8.1 Update) includes 5.0 and user applies update 5.0 to 5.1 manually.|
Windows Recovery Environment
Windows Recovery Environment (WinRE) is a set of tools based on Windows PE to help diagnose and recover from serious errors which may be preventing Windows from booting successfully. Windows RE installed along Windows Vista, Windows Server 2008, Windows 7, Windows Server 2008 R2, Windows 8 and Windows Server 2012 and may be booted from hard disks, optical media (such as an operating system installation disc) and PXE (e.g. Windows Deployment Services). A copy of Windows RE is included in the installation media of the aforementioned operating systems. It is a successor to Recovery Console.
Windows RE features include:
- Automatic Repair: Automatically finds and fixes boot errors in the Windows Vista Startup Process including corrupted Boot Configuration Data files. Prior to Windows 8, this mode is known as “Startup Repair”.
- System Restore: Same as the System Restore that is included in Windows, it allows a system’s settings to be restored to those of a previous state.
- System Image Recovery: Restores the entire system to a previous state by restoring a disk image created by Backup and Restore component of Windows. In Windows Vista, it was known as “Complete PC Restore”.
- Windows Memory Diagnostic Tool: Analyses the computer memory (RAM) for defects (not available on Windows 8)
- Windows Command Prompt: Gives command-line access to the file system, volumes and files. It can be used to run System File Checker (sfc /scannow) against an offline Windows installation and repair missing or corrupt files. Tools like Robocopy, Diskpart and DISM can be used to perform various system tasks like recovering or backing up files, managing partitions, and fix servicing-related issues respectively.
In Windows Server 2012 and Windows 8, “Refresh” or “Reset” options are also available, both of which re-install Windows from a copy of the operating system on the hard drive. The “Refresh” operation maintains files, settings, and Windows Store apps (but not other desktop applications), while “Reset” performs a clean install of Windows, optionally formatting the hard drive and perform disk wiping.
Volumes encrypted with Bitlocker can be mounted if a recovery key is available.
The Windows Recovery Environment can also be installed to a hard drive partition by OEMs, and customized with additional tools such as a separate system recovery tool for restoring the computer back to its original state. As of Windows Vista SP1, users can create their own bootable CD containing the recovery environment.
Microsoft Diagnostics and Recovery Toolset (DaRT), sold as a part of Microsoft Desktop Optimization Pack, is yet another toolset based on Windows PE that performs diagnostic and recovery on an offline copy of Windows. It can manage files, edit Windows Registry, uninstall previously installed Windows updates, scan system for malware and restore deleted files.