If you already have SolidWorks 2015 installed, you can retrieve your serial number using several official methods:
A SolidWorks 2015 serial number is a unique 25-character code used to activate and register the software. The serial number is typically provided by Dassault Systèmes, the developer of SolidWorks, or by an authorized reseller. The serial number is used to verify the authenticity of the software and ensure that it is not pirated or counterfeit. solidworks 2015 serial number list
If you already own a legal copy but are seeing "Activation Count Exceeded" or "Invalid Serial Number" errors: If you already have SolidWorks 2015 installed, you
: If you bought a digital copy, check your inbox for an email from DS SOLIDWORKS or your local Value Added Reseller (VAR). 2. Identifying Your License Type the developer of SolidWorks