or perhaps the stand alone executable will work ?
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. Wait for version 4.2.1 to be released, or just upgrade your PC Windows OS to Windows 10 home, even if it can not be upgrade to Windows 10 Pro, it is still compactible with Windows 10 generally.