Windows System and Program Files Folders

A 64-bit operating system has two versions of the program files folder and the Windows system folder (system directory). One version is intended for 32-bit files and other version is intended for 64-bit files. The name of these folders, the bitness they are intended for, and the folder path is shown in the table below:

Folder name	Bitness	Folder path	Description
SysWOW64	32	C:\Windows\SysWOW64	Windows System folder (system directory) for 32-bit libraries and executables
System32	64	C:\Windows\System32	Windows System folder (system directory) for 64-bit libraries and executables
Program Files (x86)	32	C:\Program Files (x86)	Folder for 32-bit program files
Program Files	64	C:\Program Files	Folder for 64-bit program files

On a 32-bit operating system, there is only one system folder and it is named Windows\System32. When the 64-bit operating system came along Microsoft moved the 32-bit content to Windows\SysWOW64. SysWOW64 stands for: System Windows 32-bit on Windows 64-bit.

RegSvr32.exe

Note that on a 32-bit operating system there is a RegSvr32.exe in C:\Windows\System32. On a 64-bit operating system there is a RegSvr32.exe in both C:\Windows\SysWOW64 and C:\Windows\System32. Use the correct executable to register a file.