Driver ranking in Win 2008 R2

We have a driver for which the catalog file is authenticode signed for testing purposes and running WHQL. After the WHQL certification, we receive a Microsoft signed catalog file. Now, when we try to upgrade our driver to the WHQL signed version (with the file version and date of the .sys file being the same), the upgrade fails with an error, ERROR_NO_MORE_ITEMS (0x103).

Setupapi.app.log file indicates that the same rank is assigned to both the authenticode and WHQL signed drivers while the signature types are different, snippet below:

Authenticode signed:

dvi: Created Driver Node:
dvi: HardwareID - PCI\VEN_AAAA&DEV_BBBB&SUBSYS_AAAABBBB
dvi: InfName - C:\Windows\System32\DriverStore\FileRepository\drv.inf_amd64_neutral_018b050557214acb\drv.inf
dvi: DevDesc - My Adapter
dvi: DrvDesc - My Adapter
dvi: Provider - My Company
dvi: Mfg - My Company
dvi: ModelsSec - ModelsSection.NTamd64.6.1
dvi: InstallSec - UpperFilterInstallSection.NTamd64.6.1
dvi: ActualSec - UpperFilterInstallSection.NTamd64.6.1
dvi: Rank - 0x00ff0001
dvi: Signer - Company
dvi: Signer Score - Authenticode
dvi: DrvDate - 09/28/2011
dvi: Version - 3.0.1.0

WHQL Signed:
dvi: Created Driver Node:
dvi: HardwareID - PCI\VEN_AAAA&DEV_BBBB&SUBSYS_AAAABBBB
dvi: InfName - c:\girish\test\drv.inf
dvi: DevDesc - My Adapter
dvi: DrvDesc - My Adapter
dvi: Provider - My Company
dvi: Mfg - My Company
dvi: ModelsSec - ModelsSection.NTamd64.6.1
dvi: InstallSec - UpperFilterInstallSection.NTamd64.6.1
dvi: ActualSec - UpperFilterInstallSection.NTamd64.6.1
dvi: Rank - 0x00ff0001
dvi: Signer - Microsoft Windows Hardware Compatibility Publisher
dvi: Signer Score - WHQL
dvi: DrvDate - 09/28/2011
dvi: Version - 3.0.1.0

Shouldnt the rank assigned to both these versions be different given that they are signed differently, with WHQL signature being better than authenticode?

Also, from the driver rank of 0x00ff0001, the signature score shows up as 0x00 for both types, which is different from any of the documented values. Is there a special meaning for the value 0x00?

Regards,
Girish.

Hi,
Came across this MSDN link (http://msdn.microsoft.com/en-us/library/windows/hardware/ff537759(v=vs.85).aspx), which explains the reason for driver ranks being the same on Win2k8 R2.

With this policy turned off, I see that the ranks have changed. However, I still see that the driver does not upgrade from authenticode signed to WHQL signed (with all else being the same i.e., driver version, date and size).
Is this an expected behavior given that the binary is pretty much the same? If so, where and how does the signature score fit in? Or does the signature score matter only when selecting a driver for a device which currently does not have a driver installed?

Regards,
Girish.