Hello,
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As far as I'm concerned, there is no way to get a list of win32 apis that have changed in a windows release.
Windows Server 2012 has reached end of support. You could refer to the follow links:
What's new in Windows Server 2016
What's new in Windows Server 2019
Features Removed or Deprecated in Windows Server 2016
Features removed or no longer developed starting with Windows Server 2019
For more details about a list of the reference content for the Windows application programming interface (API) for desktop and server applications, you could refer to the Doc: Windows API index
Thank you.
Jeanine
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