Antivirus software is only as good as its definitions. Kaspersky has long since stopped updating the 2015 database, meaning it cannot recognize modern ransomware, zero-day exploits, or sophisticated phishing scripts.
While Kaspersky historically supports older versions for a few years with database updates, support for the 2015 version has long since ended. Even if you install it successfully, it will not protect you against modern malware. kaspersky antivirus 2015 free download