This directory holds the 32-bit system files on the 64-bit editions of Windows. WOW stands for Windows On Windows. When a 32-bit program runs, Windows will simulate this directory as being c:\windows\system32 for backwards compatibility.
The WinSxS directory holds Windows Side-by-Side DLLs. WinSxS allows multiple versions of the same DLL (code libraries) to exist on the same system. This ensures that every application will get the DLL version they were tested and designed for. The result is improved application and system stability. See details for full directory location.
There are no known security risks in using Api-ms-win-core... assuming it has not been modified or replaced by virus or malware and it resides in the default directory. This file is installed as part of the Windows operating system.
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