I've been purchasing many Fotolia images for the last decade. But when I need to re-download some images, I can not see those in Adobe Stock My Library. Has Adobe scrapped those?
Some assets have been removed from the database by Adobe and by the author. If you see the licence, but cannot download, that means that the asset has been removed and is no more available.
Thanks, but do I have to start making sure I have all images stored on my laptop disk from now on to avoid this in the future?
Yes. If you intend to use the asset on a longterm basis, you really need to download and store a copy locally. As soon as the asset gets removed from the database, you can't download it anymore, even if you still have the right to use the asset.
I'm sorry for that, but Adobe can't allow you to (re-)download deleted assets.