After upgrade to Win 10, Calibre upgrades do not install

Recently upgraded to Windows Windows 10 from Windows 7 with Calibre 2.44 installed. After upgrade Calibre works fine, but new versions do not install. I get to the "Calibre Setup" dialog box, but the status line does not start (even after waiting a long time) and new version does not start. Have disabled virus protection, no help. Other programs install and upgrade with no problem.

THanks for the help,

Per