Before proceeding, ensure your system meets the legacy requirements:

If you are looking to install or update Illustrator CS6, follow these official guidelines: Installation Instructions Preparation

The installation package of Adobe Illustrator CS6 16.00.3264 bit appears to be a modified version of the original software. The package includes a number of files, including:

: On a 64-bit Windows system, you often have the option to install both the 32-bit and 64-bit versions. The 64-bit version allows the application to access more than 2GB of RAM, significantly improving performance for large, complex files. System Requirements for CS6