Non-genuine software issue

I am experiencing a strange software issue! I am running a version of AE CS6 which I obtained in October of 2013, version 11.0.4.2. Initially, I brought it from an reputable online vendor, then had to go to Adobe to download. I started AE today and got the message "Resolve your non-genuine software issue"...with Licensing Status "Failed". After 4 years why is the licensing status suddenly "Failed"? Any clues or remedies? Thanks....

Was running on Windows 7, upgraded to Windows 10 about 6 months ago.