SHA-2 support is available in Windows 8 / Server 2012 and up. Any OS prior to this does not natively support SHA-2 out of the box. Having said this, Microsoft tried to release a SHA-2 support patch for Windows 7 roughly 6 months ago, it was buggy and was pulled. Just last month MS decided to have another go at this and have released yet another fix for this applying to Windows 7/Server 2008 R2 but some users have also mentioned issues with this as well. You can read the details here
http://windowsitpro.com/patch-tuesday/p ... ed-3033929
Microsoft has no intention of supporting XP, Server 2003, Vista etc. with SHA-2 etc. These operating systems are legacy and will not be supported.
@Manutai
I am not able to install drivers on Windows7 x64. The same drivers work on Win XP, Win 8 , Win 7 x86.
Without
https://technet.microsoft.com/en-us/lib ... 33929.aspx it will not work on Windows 7 x64 with a SHA-2 signed driver. See the above link with issues reported. Back to your problem, the driver loads for you because Windows XP x86 and Windows 7 x86 do not enforce signature checks when loading a driver into the kernel (x64 OS do). It works on Windows 8 because SHA-2 was first introduced in this OS.
Windows 7 & Server 2008 R2 patch details:
Executive Summary
Microsoft is announcing the reissuance of an update for all supported editions of Windows 7 and Windows Server 2008 R2 to add support for SHA-2 signing and verification functionality. This update supersedes the 2949927 update that was rescinded on October 17, 2014 to address issues that some customers experienced after installation. As with the original release, Windows 8, Windows 8.1, Windows Server 2012, Windows Server 2012 R2, Windows RT, and Windows RT 8.1 do not require this update because SHA-2 signing and verification functionality is already included in these operating systems. This update is not available for Windows Server 2003, Windows Vista, or Windows Server 2008.
Recommendation. Customers who have automatic updating enabled and configured to check online for updates from Microsoft Update typically will not need to take any action because this security update will be downloaded and installed automatically. Customers who have not enabled automatic updating need to check for updates and install this update manually. For information about specific configuration options in automatic updating, see Microsoft Knowledge Base Article 294871.
For customers who install updates manually (including customers who have not enabled automatic updating), Microsoft recommends applying the update at the earliest opportunity using update management software, or by checking for updates using the Microsoft Update service. The updates are also available via the download links in the Affected Software table in this advisory.
Another negative impact worth pointing out is that if you believe you're safe from this on x86, that depends, you may not be. Some drivers even on x86 OS require signatures or their loading will be refused. Yes, that's right. An example is the more modern filtering APIs such as Vista+'s ObRegisterCallbacks for thread and process object filtering of created or duplicated handles. This API requires your driver's linker flags to include integritycheck (LINKER_FLAGS=/integritycheck) which forces the driver to be signed and validated (CI related stuff). So you see, it's not just x64 OS driver development that will suffer issues with older operating systems, this can in some circumstances affect older x86 operating systems despite them not strictly enforcing the driver signing policy with vanilla drivers.
Google wanted to make a big fuss about the "theory" of SHA-1 being broken, again this is all theoretical. Microsoft decided to jump on the bandwagon and join Google in order to phase out SHA-1, this is why effective January 1, 2016 any certificate authorities (CA) that participate in Microsoft's cross-signing program will be required to issue SHA-2 certificates exclusively. It seems that most companies jumped on this already, well before this deadline were to take effect. Now we as developers are left with this massive headache and confusion due to Microsoft's uncertainty and erratic behavior
--Iconic