我的情况是这样的：
首先用了devcon安装一个虚拟设备的驱动（bus driver），然后插入了一个虚拟设备
再拿到虚拟设备的hardwareID以后，用devcon update这个设备的驱动，但是总是failed。
devcon log内容如下：
>>> [Device Install (UpdateDriverForPlugAndPlayDevices) - {B85B7C50-6A01-11d2-B841-00C04FAD5171}\IntelDevice]
>>> Section start 2012/10/12 09:53:25.913
cmd: devcon update "C:\Users\Joe2\Desktop\NewProject\Projects\ICAEFramework\x64\Win8betaDebug\ICAEStoreBridge Package\ICAEStoreBridge.inf" {B85B7C50-6A01-11d2-B841-00C04FAD5171}\IntelDevice
dvi: {Build Driver List} 09:53:25.913
dvi: Searching for hardware ID(s):
dvi: {b85b7c50-6a01-11d2-b841-00c04fad5171}\inteldevice
dvi: Searching for compatible ID(s):
dvi: {b85b7c50-6a01-11d2-b841-00c04fad5171}\intelcompatibledevice
cpy: Policy is set to make all digital signatures equal.
dvi: {Build Driver List - exit(0x00000000)} 09:53:25.913
dvi: {DIF_SELECTBESTCOMPATDRV} 09:53:25.913
dvi: No class installer for 'Intel_Bus_Device_01'
dvi: No CoInstallers found
dvi: Default installer: Enter 09:53:25.929
dvi: {Select Best Driver}
! dvi: Selecting driver failed(0xe0000228)
dvi: {Select Best Driver - exit(0xe0000228)}
! dvi: Default installer: failed!
! dvi: Error 0xe0000228: There are no compatible drivers for this device.
dvi: {DIF_SELECTBESTCOMPATDRV - exit(0xe0000228)} 09:53:25.929
<<< Section end 2012/10/12 09:53:25.929
<<< [Exit status: SUCCESS]
请问最有可能是哪种原因导致的。
PS：我的driver是未签名的，是这个原因吗？
如果在设备管理器中手动用update driver的方法，找到我的inf，然后update是没有问题的，驱动能装上，但用devcon就是不行。
------解决思路----------------------
是什么操作系统？把系统的setupapi log文件贴出来看看。看看设备管理器安装和devcon安装的时候，对应的logo文件有什么不一样的地方。
SetupAPI Text Logs
In Windows Vista and later versions of Windows, SetupAPI supports a device installation text log (SetupAPI.dev.log) and an application installation text log (SetupAPI.app.log). The Plug and Play (PnP) manager and SetupAPI write entries to the device installation text log to provide information about operations that install devices and drivers. The PnP manager and SetupAPI write entries to the application installation text log that provide information about installation operations other than those that pertain specifically to device and driver installations.