[Archonsod]

Velusion said:
Games sell based on a number of factors... one of them is hype. This copyright protection causes negative hype - because it isn't easliy identifable. What you have is lots of pirates flooding the boards (both here and all the other game sites) with messages like "this game is buggy and broken."

Unlikely. Pretty much every mainstream game since 2000 has incorporated similar protection, and this hasn't really happened yet. I doubt you'd see this sort of thing happening, most pirates I know would simply delete the game once they encountered the bugs rather than go complaining on the forum.

The only real effect this has is to annoy some pirate users (which is a laudable enough goal) but the downside is negative hype about the stability of the game.

One would hope that the amount of legitimate users would far outnumber those of pirate users on any mainstream forum. In other words, the main negative hype would likely be on pirate sites themselves, which one could rationalise by the fact that you wouldn't be losing paying customers. Thing is, I'd expect that anyone familiar with this kind of thing would be able to figure out precisely what was happening from this.

If it wasn´t for Tombom´s explanation people would assume that dominions 3 is a cool, but buggy game. I can´t see how that helps sales.

In this specific instance then it might not, but then Illwinter have always stated they're not that bothered about sales. With a mainstream title, then you always have a legitimate fanbase who'll usually point out that the reported bug isn't affecting them (in greater numbers than the pirates one would hope).

You also presume that the customers find out that their problems are due to an illegal cd-key or bother using their legit one after the game is already installed.

Given that they'd have potential problems with multiplayer otherwise one would expect they'd switch keys as soon as they had the legit one in this case. I guess you could also assume that legit users in this situation would either find out themselves (by looking for users with similar problems) or else contact support and be told why they're having the problem.

Well I certainly don´t know if the copyprotection is part of anything else which is useful.

In this case probably not, but it's not a complicated mechanism.
In an example I gave with a more complicated mechanism (the memory/environment scan) it can detect hacks and similar cheat methods too. If you had an online game, then you'd want to implement this kind of thing as a fair play measure anyway, so it doesn't take too much (if any) modification to apply it to looking for game cracks. Similarly, back in the olden days when video or similar content needed to run from the CD while the game was being played, it doesn't take too much more effort to check the CD being played is legit.

But there have been quite a lot of reports of the bug appearing even with legit keys, so I guess the developers should have spent more time testing the code.

Depends on why it's being triggered. If your checking against a list of known suspect keys, then those people with legitimate keys who are being flagged have either had their key stolen or else have made it available to the public (breaching their EULA). Since I don't know what exactly Illwinter has implemented I can't say for sure why or what they are going to do about it. I know with other companies employing similar protection they're usually happy to issue a new key or similar if you can prove ownership.

It really makes no sense not to have a logical errormessage that tells the error is due to a bad cd-key. If you tell people that anyway via the forum, then the pirates can certainly figure it out.

Most would probably figure it out without the error message to be honest. I guess it's purely down to the preference of the authors. I suppose one thing which you would avoid is someone trying to break the protection again - if you get an error saying "wrong CD Key" then there would be nothing stopping you looking for another key until you found a working one. You could of course simply say "illegal version detected" or similar, which wouldn't tell the user precisely how it detected it.