Ultimately there is little that can be done beyond what the system already allows. Restrictions on the front end (before posting) will only throw up roadblocks for users asking legitimate questions, so making the system harder to use for new users (while beneficial for question quality) will ultimately harm the site over the long run.
The best to handle this is to limit the opportunity for incentive for posting these kind of questions, and the best way to do that is to get the question closed quickly as possible so you hopefully do not get any answers. So downvote the question, vote/flag to close, and leave a comment explaining to the user why the question is inappropriate and what can be done to fix it.
There are some more extreme members of the community that advocate downvoting answers on posts like this, and while I see the point, this can be harmful as well. The idea behind downvoting is to get the attention of the answerer so they will delete the answer or move it to a more appropriate spot (like the potential duplicate). But if it isn't deleted, a correct answer with downvotes ultimately does not benefit the site, as users coming in via Google won't understand the "politics" behind a downvoted correct answer. They will just see a downvoted answer and assume it is wrong in some way, so that practice can be almost as harmful to the site as the bad questions.