I've just upgraded to Windows 10. Why do I need a new version of Charting Companion?
Drivers are programs that let other programs talk to hardware. Printers, cameras, scanners, video cards, keyboards, mouses, disk drives etc. all require drivers. Drivers operate at the highest level of security of the operating system. A bug in a driver can bring down Windows. Malware in drivers cause maximum damage.
Microsoft introduced significant changes to the driver interface in Windows 10. Drivers must now be certified by Microsoft to insure integrity and security. Click for more details. Microsoft charges big bucks for signing. The cost must be recovered.
Progeny licenses a PDF driver from a third-party firm, who had to submit to the certification process. We need to obtain licenses for the latest, Windows-10 compatible version of the PDF driver. The license fee (to us) is in the four-figure range, a significant investment.
As of ver. 6.0.19 (7 Aug 2015), Charting Companion incorporates a Windows-10 compatible PDF driver.
But my other program(s) run on Windows 10 and didn't require an upgrade?
Your other program(s) don't include drivers. Most programs don't include drivers.