The /fastdetect parameter disables NTDETECT serial and parallel port device detection at the specified communications ports. If you do not specify a communications port, this parameter disables detection on all serial and parallel ports.

    /fastdetect[=COMx | =COMx,y,z...] 



COMx, y, z

Limits the /fastdetect parameter only to the specified ports. The x, y, and z subparameter represent one or more communication ports on the computer.


Because the /fastdetect parameter permits Plug and Play (PnP) to detect devices on these ports and prevents detection of unsupported devices, it typically results in a faster, more reliable boot.

Setup adds the /fastdetect parameter (without specified ports) to the boot entries that it creates for Windows Server 2003, Windows XP, and Windows 2000.

You can omit the /fastdetect parameter when using devices known only to the BIOS (not to Windows). For example, you should omit /fastdetect to test a port that is hidden from PnP.

This boot parameter is supported only on Windows Server 2003, Windows XP, and Windows 2000.


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

multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect=COM2

Bootcfg Commands

bootcfg /raw "/fastdetect" /A /ID 1
bootcfg /raw "/fastdetect=COM2" /A /ID 2



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