Hello, I installed my Premiere Pro CS6, using the original disc and it's asking me to activate by logging in. But when I click on "Sign-in", I'm getting this error attached.
That is incorrect as of May 2019. Adobe now restricts older version availability to the major version that precedes the current version when downloading via the Creative Cloud front end. That means version 23 (2023) is now the absolute oldest version that can be downloaded. All other older versions are now permanently removed from Adobe's servers.