Sage maintains archived full product downloads for users who need to reinstall for data conversion purposes.
Direct links for the Canadian version (v2015.3) are sometimes available via community support threads or the Sage CA Support Portal .
Once you have the .exe installer file (often named Sage50_2015.exe ), follow these steps: Download Sage 50 2015.3 Full Product
You can search for "Sage 50 US Downloads" on the Sage North America Knowledgebase to find the 2015.3 full product package.
The safest way to download Sage 2015 is through official Sage portals to ensure the installer is secure and authentic.