Adobe InDesign CS3

The only time I've sold software was to someone local who could come in person to pick it up, and even try it on their laptop if they wanted to. No shipping involved.

Yes, it is old, but someone with older equipment might be happy to get it at a good price.

i doubt there is much money to make back on selling a computer program that is so old. probably spend more in shipping than what its worth.

Well, if it's never been registered, won't need to go through the hassle of transferring license.  paulinea12814672 could try craigslist or even amazon.  There are other software ads on eBay, so not sure why it was removed. You could just give it another try, maybe with different wording.

It is legal for you to sell it. By filling out forms on Adobe web site, you can legally transfer your license.

I can't comment on the legality (did you re-use the same license number for your later updates, for instance?) but practically speaking, CS3 is 11 years old. Which is positively ancient, in terms of computer software – there have been eight major new releases since then.

You don't mention what OS this is for, and while I already know for a fact that it simply will not run on a modern version of Mac OS X, I would also not vouch for it running smoothly on a modern version of Windows. Which, all in all, would make it a pretty hairy purchase.

In a couple of decades, your "sealed, original packaged" software may acquire antique value though.

While it is not exactly forbidden, there are much fake sales on e-bay. So it's probably more trouble to sell then it's worth the hassle. Also as cruel as it may sound, the software costing at the time several hundreds of dollars is now virtually worthless.