Hi all, We have developed a kernel mode drives which runs as a part of an application and it does not need a catalog file. To sign this driver Do we have to buy the cross certificate from Microsoft ? Please let me know the procedure. We did the following step to sign the driver. a) download the cross certificate (MSCV-VSClass3.cer) from the following link http://msdn.microsoft.com/en-us/windows/hardware/gg487315.aspx b) Installed the certificate. c) Typed the following command from WINDDK command prompt. Paths are valid. SignTool sign /v /ac MSCV-VSClass3.cer /s my /n "Our Comapny Name"/t http://timestamp.verisign.com/scripts/timestamp.dll AMD64\ourdriver.sys It gives SignTool Error: No certificates were found that met all the given criteria. We have the crtificate from COMODO which has only code signing capability. Thanks & Regards Parna Sanyal