Because Windows 8 is a legacy platform, you cannot simply download the "latest" version. Follow these steps to obtain a compatible version:
SolidWorks Download for Windows 8: Complete Compatibility & Setup Guide
Log in to the SolidWorks Downloads page using your serial number or subscription account. solidworks download windows 8
Navigate to the "Downloads" or "Software and Tools" section. You will need to filter for SolidWorks 2018 or earlier to find a version that will install on your OS.
It is recommended to download the latest available Service Pack (e.g., 2018 SP5 ) for the best stability on older hardware. Because Windows 8 is a legacy platform, you
Most versions (specifically starting with 2014 SP1) require Windows 8.1 rather than the base Windows 8.
If you cannot find older media online, contact your Value Added Reseller (VAR) or use services like GoEngineer , which provide links for legacy versions back to 2012. System Requirements | SOLIDWORKS You will need to filter for SolidWorks 2018
Not all versions of SolidWorks are compatible with Windows 8 or 8.1. According to official SolidWorks System Requirements , the support window for this OS is narrow: