Adobe Acrobat Pro 2015 Classic "browser or OS no longer supported"
To resolve this issue, follow these steps:
Quit Packager, if it is running.
Download the following zip archive
The above zip archive contains the following executable:
AASIapp.exe
Copy (and overwrite) the extracted executable to the following location:
C:\Program Files (x86)\Common Files\Adobe\OOBE\PDApp\P7
https://helpx.adobe.com/enterprise/kb/ccp-windows-sign-in-issue.html