Bcdedit

Bcdedit

Bcdedit

Updated: September 28, 2007

Boot Configuration Data (BCD) files provide a store that is used to describe boot applications and boot application settings. The objects and elements in the store effectively replace Boot.ini.

BCDEdit is a command-line tool for managing BCD stores. It can be used for a variety of purposes, including creating new stores, modifying existing stores, adding boot menu parameters, and so on. BCDEdit serves essentially the same purpose as Bootcfg.exe on earlier versions of Windows, but with two major improvements:

Exposes a wider range of boot parameters than Bootcfg.exe.
Has improved scripting support.

Note
Administrative privileges are required to use BCDEdit to modify BCD.

BCDEdit is the primary tool for editing the boot configuration of Windows Vista and later versions of Windows. It is included with the Windows Vista distribution in the %WINDIR%\System32 folder.

BCDEdit is limited to the standard data types and is designed primarily to perform single common changes to BCD. For more complex operations or nonstandard data types, consider using the BCD Windows Management Instrumentation (WMI) application programming interface (API) to create more powerful and flexible custom tools.

Syntax

BCDEdit /Command [<Argument1>] [<Argument2>] ...

Parameters

General BCDEdit Command-Line Option

Option	Description
/?	Displays a list of BCDEdit commands. Running this command without an argument displays a summary of the available commands. To display detailed help for a particular command, run bcdedit /? <command>, where <command> is the name of the command you are searching for more information about. For example, bcdedit /? createstore displays detailed help for the Createstore command.

Parameters that Operate on a Store

Option	Description
/createstore	Creates a new empty boot configuration data store. The created store is not a system store.
/export	Exports the contents of the system store into a file. This file can be used later to restore the state of the system store. This command is valid only for the system store.
/import	Restores the state of the system store by using a backup data file previously generated by using the /export option. This command deletes any existing entries in the system store before the import takes place. This command is valid only for the system store.
/store	This option can be used with most BCDedit commands to specify the store to be used. If this option is not specified, then BCDEdit operates on the system store. Running the bcdedit /store command by itself is equivalent to running the bcdedit /enum active command.

Parameters that Operate on Entries in a Store

Parameter	Description
/copy	Makes a copy of a specified boot entry in the same system store.
/create	Creates a new entry in the boot configuration data store. If a well-known identifier is specified, then the /application, /inherit, and /device parameters cannot be specified. If an identifier is not specified or not well known, an /application, /inherit, or /device option must be specified.
/delete	Deletes an element from a specified entry.

Parameters that Operate on Entry Options

Parameter	Description
/deletevalue	Deletes a specified element from a boot entry.
/set	Sets an entry option value.

Parameters that Control Output

Parameter	Description
/enum	Lists entries in a store. The /enum option is the default value for BCEdit, so running the bcdedit command without parameters is equivalent to running the bcdedit /enum active command.
/v	Verbose mode. Usually, any well-known entry identifiers are represented by their friendly shorthand form. Specifying /v as a command-line option displays all identifiers in full. Running the bcdedit /v command by itself is equivalent to running the bcdedit /enum active /v command.

Parameters that Control the Boot Manager

Parameter	Description
/bootsequence	Specifies a one-time display order to be used for the next boot. This command is similar to the /displayorder option, except that it is used only the next time the computer starts. Afterwards, the computer reverts to the original display order.
/default	Specifies the default entry that the boot manager selects when the timeout expires.
/displayorder	Specifies the display order that the boot manager uses when displaying boot parameters to a user.
/timeout	Specifies the time to wait, in seconds, before the boot manager selects the default entry.
/toolsdisplayorder	Specifies the display order for the boot manager to use when displaying the Tools menu.

Parameters that Control Emergency Management Services

Parameter	Description
/bootems	Enables or disables Emergency Management Services (EMS) for the specified entry.
/ems	Enables or disables EMS for the specified operating system boot entry.
/emssettings	Sets the global EMS settings for the computer. /emssettings does not enable or disable EMS for any particular boot entry.

Parameters that Control Debugging

Parameter	Description
/bootdebug	Enables or disables the boot debugger for a specified boot entry. Although this command works for any boot entry, it is effective only for boot applications.
/dbgsettings	Specifies or displays the global debugger settings for the system. This command does not enable or disable the kernel debugger; use the /debug option for that purpose. To set an individual global debugger setting, use the bcdedit /set <dbgsettings> <type> <value> command.
/debug	Enables or disables the kernel debugger for a specified boot entry.

Examples

For examples of BCDEdit, see the Windows Hardware Developer Center Web site.