Older, perpetual license installation of Acrobat is requesting Adobe ID to sign in.
I have some subscriptions to the new version Adobe Acrobat DC, but I also have some old installations of DC 2015 that were purchased as a perpetual license with a license key. Suddenly some of these perpetrual licensed installations started asking for Adobe ID, and they will not accept anything I give it. It is as if Adobe now believes that this is a subscription installation. What has happened here? Has Adobe revoked older perpetual licensed installations?