Also, I would like to remind that, Hysys is a commercial software, you might need to purchase it or get a trial version.
Before installing, ensure your system meets the minimum requirements for Hysys. AspenTech typically provides system requirements for each software version. Download Hysys 32 Windows 7 64 Bit-
You're looking to download Hysys 32 on a Windows 7 64-bit system. Also, I would like to remind that, Hysys