Windows 7 includes a few improvements to startup. Most
significantly, setup now automatically installs Windows Recovery
Environment (WinRE). WinRE, which includes the Startup
Repair tool, was available for Windows Vista, but it was not
automatically installed. IT professionals could configure the required
partition and install the tools to the computer's hard disk, but this
was not done by default. Therefore, most users started WinRE from the
Windows Vista setup DVD. With Windows 7, users can start WinRE directly
from the hard disk if Windows cannot start, and Windows startup will
automatically open WinRE if Windows fails to start. If the hard disk is
damaged, users can still start WinRE from the Windows 7 DVD.
Several aspects of the Windows
Vista and Windows 7 startup process have changed when compared to
Windows XP. Most significantly, Ntldr (the feature of Windows XP that
displayed the boot menu and loaded the Windows XP kernel) has been
replaced by the Windows Boot Manager and the Windows Boot Loader. The Boot.ini
file (a file that contains entries describing the available boot
options) has been replaced by the boot configuration data (BCD) registry
file. Ntdetect.com functionality has been merged into the kernel, and
Windows Vista no longer supports hardware profiles. In fact, hardware
profiles are no longer required: Windows will automatically detect
different hardware configurations without requiring administrators to
explicitly configure profiles. Finally, the command-line recovery
console has been replaced by the graphical WinRE, which simplifies
troubleshooting.
The
BCD registry file replaces the Boot.ini files used in Windows XP and
earlier versions of Windows to track operating system locations, and it
allows for a variety of new Windows Vista and Windows 7 features,
including the Startup Repair tool and the Multi-User Install shortcuts.
The BCD is stored in a data file that uses the same format as the
registry and is located on either the Extensible Firmware Interface (EFI)
system partition (for computers that support EFI) or on the system
volume. On BIOS-based operating systems, the BCD registry file is
located at \Boot\Bcd on the active partition. On EFI-based operating
systems, the BCD registry file is located in the \EFI\Microsoft\Boot\
folder on the EFI system partition.
The BCD registry file can contain the following types of information:
Entries that describe Windows Boot Manager (\Bootmgr) settings
Entries to start the Windows Boot Loader (\Windows\System32\WinLoad.exe), which can then load Windows Vista
Entries
to start Windows Resume Application (\Windows\System32\WinResume.exe),
which can then restore Windows Vista from hibernation
Entries to start Windows Memory Diagnostic (\Boot\MemTest.exe)
Entries to start Ntldr to load previous versions of Windows
Entries to load and execute a Volume Boot Record, which typically starts a non-Microsoft boot loader
Additionally, you can add more entries to load custom applications, such as recovery tools.
You can modify the BCD registry file in several different ways:
Startup And Recovery With the Startup
And Recovery dialog box (available on the Advanced tab of the System
Properties dialog box), you can select the default operating system to
start if you have multiple operating systems installed on your computer.
You can also change the time-out value. This dialog box has changed
very little when compared to Windows XP; however, it now changes the BCD
registry file instead of the Boot.ini file.
System Configuration utility (Msconfig.exe)
Msconfig.exe is a troubleshooting tool that you can use to configure
startup options. The Boot tab in Windows 7 provides similar
functionality to the Boot.ini tab in Windows XP, such as starting in
safe mode, enabling a boot log, or disabling the graphical user
interface (GUI).
BCD Windows Management Instrumentation provider
The BCD Windows Management Instrumentation (WMI) provider is a
management interface that you can use to script utilities that modify
BCD. This is the only programmatic interface available for BCD; you
should always use this interface rather than attempting to access the
BCD registry file directly. For more information, see "BCD WMI Provider Classes" at http://msdn2.microsoft.com/en-us/library/aa362675.aspx.
BCDEdit.exe
BCDEdit.exe is a command-line utility that replaces Bootcfg.exe in
Windows XP. BCDEdit can be run from within Windows 7 at an
administrative command prompt, from within Windows RE or even from
within earlier versions of Windows (if the BCDEdit.exe file is
available). BCDEdit provides more configuration options than the Startup And Recovery dialog box.
Non-Microsoft tools Third-party software vendors have released tools to simplify editing the BCD registry file, including:
You
cannot use Bootcfg.exe to modify BCD. However, Bootcfg.exe will remain
in the operating system to support configuring older operating systems
that might be installed on the same computer.
For EFI computers,
BCDEdit also replaces NvrBoot. In previous versions of Windows, you
could use NvrBoot to edit the EFI boot manager menu items.
Windows Vista and Windows 7 replace the Recovery Console troubleshooting tool with the new System
Recovery tool (part of WinRE). Typically, you will start the tool by
pressing F8 before starting Windows and then choosing Repair Your
Computer from the Advanced Boot Options screen. If that choice is not
available because the hard disk has failed, you can start the tool by
starting from the Windows 7 DVD and then clicking Repair Your Computer
(after configuring the language options). This loads a specialized
version of Windows Preinstallation Environment (Windows PE) and then
displays the System
Recovery tool.
The System Recovery tools provide access to the following tools:
Startup Repair
The Startup Repair tool can solve many common startup problems
automatically. Startup Repair performs an exhaustive analysis to
diagnose your startup problems, including analyzing boot sectors, the
Boot Manager, disk configuration, disk integrity, BCD registry file
integrity, system file integrity, registry integrity, boot logs, and
event logs. It will then attempt to solve the problem, which may involve
repairing configuration files, solving simple disk problems, replacing
missing system files, or running System Restore to return the computer
to an earlier state. Because Startup Repair performs these tasks
automatically, you can solve startup problems much faster than
performing the analysis and repair manually.
System Restore
Windows automatically captures system state before installing new
applications or drivers. You can later use the System Restore tool to
return to this system if you experience problems. Because System Restore
is available from the System Recovery tools, you can use System Restore to repair problems that prevent Windows Vista or Windows 7 from booting. Startup
Repair can prompt you to initiate a System Restore, so you might never
need to access this tool directly.
System Image Recovery
You use this tool to initiate a complete restore of the system hard
disk. However, because any files saved since the last backup will be
lost, you should use this only as a last resort.
Windows Memory Diagnostic
The Windows Memory Diagnostics tool performs an automated test of the
reliability of your computer's memory.
Command Prompt From the Command
Prompt tool, you have access to many standard command-line tools. Some
tools will not work properly, however, because Windows Vista is not
currently running. For example, because WinRE does not include
networking capabilities, network tools will not function correctly.
However, several tools in WinRE are useful:
BCDEdit.exe for making changes to the BCD registry file
Diskpart.exe for viewing and changing disk partitioning
Format.exe for formatting partitions
Chkdsk.exe for finding and resolving some disk problems (note that Chkdsk cannot add events to the event log when started from System Recovery tools)
Notepad.exe for viewing log files or editing configuration files
Bootsect.exe
(available on the Windows 7 DVD in the \Boot\ folder) for updating the
master boot code for hard disk partitions to switch between the Windows 7
Boot Manager and Ntldr, used by Windows XP and earlier versions of
Windows
Bootrec.exe for manually repairing disk problems if Startup Repair cannot fix them
Windows Boot Performance Diagnostics
Sometimes,
Windows might start correctly but might take an unusually long time to
do so. Such a problem can be difficult to troubleshoot because there's
no straightforward way to monitor processes while Windows is starting.
To help administrators identify the source of startup performance
problems and to automatically fix some problems, Windows 7 includes Windows Boot Performance Diagnostics.
You
can use the Group Policy settings to manage Windows Boot Performance
Diagnostics in an Active Directory Domain Services (AD DS) environment.
In the Computer Configuration\Policies\Administrative
Templates\System\Troubleshooting and Diagnostics\Windows Boot
Performance Diagnostics node, edit the Configure Scenario Execution
Level policy. When this policy is enabled, you can choose from the
following two settings:
Detection And Troubleshooting Only Windows
Boot Performance Diagnostics will identify startup performance problems
and will add an event to the event log, allowing administrators to
detect the problems and manually troubleshoot them. Windows Boot Performance Diagnostics will not attempt to fix the problems, however.
Detection, Troubleshooting, And Resolution
Windows Boot Performance Diagnostics will identify startup performance
problems and automatically take steps to attempt to alleviate the
problems.
If you disable the setting, Windows Boot
Performance Diagnostics will neither identify nor attempt to resolve
startup performance problems. For Windows Boot Performance Diagnostics
to function, the Diagnostic Policy Service must be running.
Settings for Windows
Shutdown Performance Diagnostics, which function similarly to the
Windows Boot Performance Diagnostics, are located in the Computer
Configuration\Policies\Administrative Templates\System\Troubleshooting
And Diagnostics\Windows Shutdown Performance Diagnostics node.