Signed driver appears as unsinged in device manager

Question

Our software using signed drivers, everything works correctly. But for some reasons this driver appear as unsigned in device manager. In our case this makes unwanted warnings in failover cluster validation reports on Windows Server, which may make our customers a bit confused. What may cause such behaviour? Thanks.

Answer 1

Found solution!
The problem was in missing cross certificate
Signing should look like this:

signtool sign /v /f "Cert.pfx" /p pwd /ac "Cross.cer" /t "http://timestamp.server" driver.sys

Cross certificates itself can be found here - http://msdn.microsoft.com/en-us/library/windows/hardware/dn170454(v=vs.85).aspx