C# - How to get Program Files (x86) on Windows 64 bit

The function below will return the x86 Program Files directory in all of these three Windows configurations:

• 32 bit Windows
• 32 bit program running on 64 bit Windows
• 64 bit program running on 64 bit windows

 

static string ProgramFilesx86()
{
    if( 8 == IntPtr.Size 
        || (!String.IsNullOrEmpty(Environment.GetEnvironmentVariable("PROCESSOR_ARCHITEW6432"))))
    {
        return Environment.GetEnvironmentVariable("ProgramFiles(x86)");
    }

    return Environment.GetEnvironmentVariable("ProgramFiles");
}

If you're using .NET 4, there is a special folder enumeration ProgramFilesX86:

Environment.GetFolderPath(Environment.SpecialFolder.ProgramFilesX86)

Environment.GetEnvironmentVariable("PROGRAMFILES(X86)") ?? Environment.GetFolderPath(Environment.SpecialFolder.ProgramFiles)