BCDEdit Options Reference

Boot entry parameters, or boot parameters, are optional, system-specific settings that represent configuration options. You can add boot parameters to a boot entry for an operating system.

This section describes the boot options for Windows 8.1, Windows 8, Windows 7, and Windows Vista, that are related to developing, testing, and debugging drivers on computers with x86-based and x64-based processors. You can add these parameters to the boot entries for Windows operating systems.

Note  Before setting BCDEdit options you might need to disable or suspend BitLocker and Secure Boot on the computer.

In this section

TopicDescription

BCDEdit /bootdebug

The /bootdebug boot option enables or disables boot debugging of the current or specified Windows operating system boot entry.

Note  Before setting BCDEdit options you might need to disable or suspend BitLocker and Secure Boot on the computer.

BCDEdit /dbgsettings

The /dbgsettings option sets or displays the current global debugger settings for the computer. To enable or disable the kernel debugger, use the BCDEdit /debug option.

Note  Before setting BCDEdit options you might need to disable or suspend BitLocker and Secure Boot on the computer.

BCDEdit /debug

The /debug boot option enables or disables kernel debugging of the Windows operating system associated with the specified boot entry or the current boot entry.

Note  Before setting BCDEdit options you might need to disable or suspend BitLocker and Secure Boot on the computer.

BCDEdit /deletevalue

The BCDEdit /deletevalue command deletes or removes a boot entry option (and its value) from the Windows boot configuration data store (BCD). Use the BCDEdit /deletevalue command to remove options that were added using BCDEdit /set command. You might need to remove boot entry options when you are testing and debugging your driver for Windows Vista, Windows 7, Windows 8, and later versions of Windows.

BCDEdit /ems

The /ems option enables or disables Emergency Management Services (EMS) for the specified operating system boot entry.

BCDEdit /emssettings

The /emssettings option sets the global Emergency Management Services (EMS) settings for the computer. To enable or disable EMS, use the /ems option. The /emssettings option does not enable or disable EMS for any boot entry.

BCDEdit /set

The BCDEdit /set command sets a boot entry option value in the Windows boot configuration data store (BCD) for Windows Vista, Windows 7, Windows Server 2008, Windows 8, Windows 8.1, Windows Server 2012, and Windows Server 2012 R2. Use the BCDEdit /set command to configure specific boot entry elements, such as kernel debugger settings, memory options, or options that enable test-signed kernel-mode code or load alternate hardware abstraction layer (HAL) and kernel files. To remove a boot entry option, use the BCDEdit /deletevalue command.

 

Mapping Boot.ini Options to BCDEdit Options and Elements

The following table provides a mapping from the boot options used in operating systems prior to Windows Vista (in Boot.ini), to the BCDEdit options and the BCD elements used in Windows Vista and later versions of Windows. For information about the BCD boot elements see BCD Reference on MSDN.

Boot.iniBCDEdit option BCD element type

/3GB

increaseuserva

BcdOSLoaderInteger_IncreaseUserVa

/BASEVIDEO

vga

BcdOSLoaderBoolean_UseVgaDriver

/BOOTLOG

bootlog

BcdOSLoaderBoolean_BootLogInitialization

/BREAK

halbreakpoint

BcdOSLoaderBoolean_DebuggerHalBreakpoint

/CRASHDEBUG

/dbgsettings /start

/DEBUG, BOOTDEBUG

/debug

/bootdebug

BcdLibraryBoolean_DebuggerEnabled

/DEBUG

/debug

BcdOSLoaderBoolean_KernelDebuggerEnabled

/DEBUG, /DEBUGPORT=

/dbgsettings

BcdLibraryInteger_DebuggerType

/DEBUGPORT=

/dbgsettings

BcdLibraryInteger_SerialDebuggerPort

BcdLibraryInteger_SerialDebuggerBaudRate

BcdLibraryInteger_1394DebuggerChannel

BcdLibraryString_UsbDebuggerTargetName

BcdLibraryInteger_DebuggerNetHostIP

BcdLibraryInteger_DebuggerNetPort

BcdLibraryBoolean_DebuggerNetDhcp

BcdLibraryString_DebuggerNetKey

/EXECUTE

nx

BcdOSLoaderInteger_NxPolicy

/FASTDETECT

/HAL=

hal

BcdOSLoaderString_HalPath

/KERNEL=

kernel

BcdOSLoaderString_KernelPath

/MAXMEM=

truncatememory

BcdLibraryInteger_TruncatePhysicalMemory

/NODEBUG

/debug

/NOEXECUTE

nx {

BcdOSLoaderInteger_NxPolicy

/NOGUIBOOT

quietboot

BcdOSLoaderBoolean_DisableBootDisplay

/NOLOWMEM

nolowmem

BcdOSLoaderBoolean_NoLowMemory

/NOPAE

pae

BcdOSLoaderInteger_PAEPolicy

/ONECPU

onecpu

BcdOSLoaderBoolean_UseBootProcessorOnly

/PAE

pae

BcdOSLoaderInteger_PAEPolicy

/PCILOCK

usefirmwarepcisettings

BcdOSLoaderInteger_UseFirmwarePciSettings

/REDIRECT

/ems

/emssettings [ BIOS ] |

[ EMSPORT:{port} | [EMSBAUDRATE: {baudrate}] ]

BcdOSLoaderBoolean_EmsEnabled

/SOS

sos

 

 

 

Send comments about this topic to Microsoft

Show:
© 2014 Microsoft. All rights reserved.