Previously, we used SHA1 encryption for certification, but that type of encryption was compromised and because of that it was deprecated and our certificate provider does not support that level of security anymore. Now we use SHA256 encryption for our ASIO Driver Certification, which can create a problem for users with Windows 7 (for example the Driver is no longer recognized as signed).
Win 7 was not released with SHA256 support, so If Win 7 users are encountering an issue that manifests itself in a system without the update as Driver Digital Signature issue, this is because their system does not support SHA-2 encryption and it does not recognize the driver as signed.
Microsoft released a security update with SHA-2 support to address that. In order to install the security update Windows users must have Service Pack 1 (SP1) already installed on their system and download the Windows Security Update:
The PC needs to be restarted in order to complete the installation.
This update is needed for Win 7 users only, because all later windows versions were released with SHA256 support.