This is not about the one (be it standalone, Windows Installer or Portable version) you downloaded, from Electrum release note on GitHub that you just posted explains it all, upgrade your PC OS to Windows 10 Pro, even if it can not be upgrade to Windows 10 Pro, it is still compactible with Windows 10 generally. It is advisable to use latest OS version and Windows do not even have support for Windows 7 again which should be a reason for you to to upgrade to avoid vulnerability.