Microsoft now prefers SHA-2 algorithm to patch Windows legacy OS versions
Microsoft has said in an official statement that it will be ruling out the support for SHA-1 algorithm and will migrate to SHA-2 hash algorithm for code-signing purpose.
So, Customers running legacy OS versions (Windows 7 SP1, Windows Server 2008 R2 SP1 and Windows Server 2008 SP2) will be required to have SHA-2 code signing support installed on their devices by July 2019. Any devices without SHA-2 support will not be offered Windows updates after July 2019. Microsoft will be releasing updates that introduces SHA-2 code sign support.
The tech-giant also said that the migration process will be happening in stages, and support will be delivered in standalone updates.
Here is the complete migration timeline for updates that introduces SHA-2 code sign support:
https://support.microsoft.com/en-in/help/4472027/2019-sha-2-code-signing-support-requirement-for-windows-and-wsus
Update 1:
Microsoft has introduced the SHA-2 code signing support for Windows 7 SP1, and Windows server 2008 R2 SP1 alongside March's Patch Tuesday updates.
Look for Patch IDs:26266 to 26268 in Desktop Central to install the updates.