Your referenced reply seems to refer to downloaded Adobe products.
I thought I read elsewhere that CS6 was on life support but not dead yet. Perhaps it is after all.
My PS CS5 is boxed Adobe DVD media with serial number originally purchased new by me. It installs OK on my new computer - but when entering the serial number to activate it says it's invalid. I've tried the steps on the Adobe link but no help.
Be sure to remain signed in with your Adobe ID before accessing the link below -you must also allow 'cookies' in your web browser for this to work https://helpx.adobe.com/contact/support.html for chat or https://helpx.adobe.com/contact/phone.html -click the chat icon at the bottom right of the page to open a chat session -the chat icon looks like '3 dots inside a circle' at the lower right -type AGENT into the chat window to connect directly to a person rather than the AI Do be aware that Adobe's staffing is impacted by the virus, so wait times are long