Trying to Install Photoshop CS3 on PC

I installed CS3 on a Windows 10 system yesterday. It is indeed perfectly functional (with a little tweaking of compatibility settings), a fast, powerful editor that works as well as it ever did. I seem to be one of the lucky few who stumbled across the activation-free version of CS3 that Adobe briefly made available to licence holders after the activation servers were taken down. They set up a support page where you could enter your original serial number, and receive an activation-free version of the installer with a new serial number in return. I was impressed by this response at the time - Adobe were clearly looking after their customers. Unfortunately, the page vanished without warning, as silently as it had appeared, and there now seems to be no legal means of installing the software you paid for on a new system, even if it's the £2000 Master Collection.

A common response to queries about CS3 on this forum seems to be to lock the thread with [CS3 is dead] appended to the title, to remind us what year it is (how could we forget?), to suggest it's our own fault for not upgrading sooner (it seems we should be grateful it worked for as long as it did), to point to the small print that spells out that Adobe has all the power in this relationship, and to inform us we should be using CC (yes, we've heard of it). Although nobody on this forum can change Adobe's business decisions, a little empathy for the plight of fellow users might go a long way, and perhaps make the affected posters more inclined to upgrade rather than checking out the (increasingly good) competition.