Hi. Just ran across the "correct" answer to my question re "Had CS6, tried to reinstall on new PC and couldn't find S/N" looking through email in my folder. Ultimately found S/N but still didn't work. Was told that Adobe sold batches of S/Ns to dealers who later sold them on eBay, and Adobe eventually disallowed same. The "correct" answer is copied below, and I wanted to bring up a couple points none of the previous responses did. Below is the "correct" answer:
Adobe Community Professional , Jul 12, 2021
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That's a shame. You get what you pay for, I guess.
Goodbye & good luck with your future endeavors.
Nancy O'Shea, Adobe Product User & Community Professional
Alt-Web Design & Publishing ~ Web : Print : Graphics : Media
Ms. O'Shea,
That seems rather self-congratulatory to me. Those were legitimate serial numbers, which Adobe SOLD to a dealer who later legitimately sold on eBay. Adobe later disallowed the LEGITIMATE sale and S/Ns, apparently because the dealer sold them for a lower profit margin than Adobe preferred, and because a lot of people have been hanging on to CS6 because it was the last version of Adobe's software before Adobe went to the RENTAL model, and a lot of people object to renting software and paying, in the end, much more than they used to pay. Adobe's marketing apparently decided to try to FORCE this group of customers to switch to CC by disallowing their S/Ns. Again, these were LEGITIMATE serial numbers, and the sales on eBay were LEGITIMATE sales. Adobe's RETROACTIVE disallowance of those S/Ns, YEARS later, was NOT HONORABLE. Fortunately, there ARE alternatives to the Adobe products I use, and many people have been quitting Adobe for such alternatives. It's your own fault.
TMHatter