said 8 months, 4 weeks ago:
It really depends on the situation and yes, there are best practices. If it’s a public matter, meaning something that many people are asking, complaining or know about, a public response may be best.
If it’s one customer that is having an issue with something, it’s better to contact them directly to help fix the problem. You can also reply to the message the publicly posted with something like “I have sent you a private message, I look forward to helping you” or something to that effect so others see that the complaint is being resolved.
You never want to ignore your customers or fans on social networks. It can cause a lot more damage in the long run. You really need to look at the situation and use your best judgement.