It seems that "misconfigure" is an acceptable word by Wiktionary standards.
I believe that if your formal communication involves writing to or talking with somebody who has tried to "configure" something, the message will be clear, and thus, the usage acceptable. If you are in a context where there is danger of miscommunication or misunderstanding, then you might prefer the "configured incorrectly" version. However, note that in the latter, you run the risk of somebody misinterpreting it to mean that there was a single "correct" configuration that was possible. Hence, I believe, in general misconfigure(d) is more accurate, and thereby more preferable.