Let's take this question as example.
I think the best in this case would be to contact the support of the company and identify/fix problems with them. I'd tell the user to contact support and see if they can fix it.
Did you consider contacting support? This seems like a problem on the developers end, breaking the serial key validation.
But are such comments/answers really appropriate and helpful?
I think "Contact Support" is a fine answer when appropriate - if it's a known problem that can only be solved by contacting support, then hey, that's the answer. Sometimes people ask questions with simple answers, and that's okay.
Closing questions because the answer is "seek support via the official channels" is problematic, however. If the answer is something that is obvious - then downvote the question.
What if there's a workaround that is discovered? Isn't that useful information that people should be allowed to post as an answer? What if "contact support" isn't an obvious answer - in some cases defective disks cause game bugs and the best solution is to call the company and get a replacement. This is not a bad question, or one that does not deserve an answer.
Close the question if and only if allowing it to be answered would be bad.
For instance:
"I'm getting this particular error X every time I try to launch the installer" - The answer may be "contact support" in the FAQ for the game at the company's website, in which case we'd say contact support. If this is something that shows up immediately in a google search or so on, you might opt to downvote.
"I need a CD key/install files for game X because I lost mine" - Contact support is the correct answer, but leaving this open might encourage people to post pirated serial numbers or other shenanigans, so close it.
There are some questions that we're just flat out incapable of providing an answer for.
We can't restore your hacked Diablo 3 account and gold, but Blizzard support can.
We can't help you get a refund or new serial code because something went screwy when you bought a game, etc.
If I has my druthers, these sort of unanswerable questions would all be closed and subsequently deleted but an answer directing them to the appropriate place is the next best thing.
I mean, honestly, what the hell else are we supposed to do?
You ask if such comments or answers are really helpful, but the alternative isn't some mythical 'better' answer, it's no answer at all.
I would say you should treat this situation like any other. If the question seems like it can be answered by technical support, you should put that in a comment. If you know that technical support can solve their problem, you should put that in an answer.
