I have been using JTAlert for several years now and cannot imagine operating the JT65/JT9 modes without it...thank you again for your efforts in producing this software!
My Computer #1 is running Windows 10 Pro with the big November update (to version 1511). That update required me to re-install some of my ham radio software, but not JTAlert as I recall.
I had problems on Computer #1 when trying to update JTAlert to 2.6.24 and 2.6.25 however. The installer just locks-up and I have to re-start unless I go to "Properties" with a right-click on the installer icon and change it to Windows 7 compatibility. Once installed, JTAlert runs fine on this machine.
Computer #2 is used exclusively for ham radio applications and is running Windows 10 Pro, but without the November update. JTAlert 2.6.25 installs with no problems on this machine.
This experience points to some sort of incompatibility between the JTAlert installer and Windows 10 Pro version 1511 (November update).
Again, JTAlert is working fine for me on both computers once I overcame the installation difficulties on Computer #1.