The /crashdebug parameter establishes a kernel debugger connection, but does not enable debugging unless a bug check occurs. Until then, the port that is usually reserved for debugging is free for other uses.

This option is designed for Windows 2000 and Windows XP. For Windows Server 2003, use the /debug=disable parameter. For details, see /debug.

    /crashdebug [/debugport=COMx] [/baudrate=BaudRate] 




Specifies the serial port used by the kernel debugger for crash-only debugging.


Specifies a communications port on the computer. Valid values for COMx are any valid COM port, such as COM1 or COM2. The default is the highest enumerated port.


Specifies the speed of the kernel debugger connection.


Specifies the speed of the kernel debugger connection in bits per second (BPS). Valid values for BaudRate are 9600, 19200, 38400, 57600, and 115200. The default is 19200.


This parameter is useful for debugging random kernel errors.

If a boot entry includes both /debug and /crashdebug, the /debug parameter is ignored.


multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /crashdebug

multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /crashdebug /debugport=COM1 /baudrate=57600

Bootcfg Commands

bootcfg /raw "/crashdebug" /A /ID 1
bootcfg /raw "crashdebug /debugport=COM1 /baudrate=57600" /A /ID=2



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