After installing Adobe CS3 on my older Mac after a hard drive crash, I found I was unable to complete activation because Adobe's server for CS3 activations had been retired. Thankfully I was able to install CS4 on the machine and it activated! And this version still supports the old file types I need to access. I was able to use the date change workaround suggested by another forum member to auto-update.
Now that leads to the next question. How can I find out when Adobe is going to discontinue online activation for CS4 so I can plan accordingly? I did not get the memo on CS3 until it was too late. (FYI - I have a Creative Cloud subscription, but I still need access to older versions of the software to support customer data.)
CS3's activation servers failed. Nobody plans for that, it just happens. CS4, 5 & 6 are on life support. But as long as you never need to re-install or upgrade your computer you should be golden for another 10 years.
Nancy O'Shea, Adobe Product User & Community Professional Alt-Web Design & Publishing ~ Web : Print : Graphics : Media