Michigan Compiled Laws, Chapter 339. Occupational Code § 339.2512a

Sec. 2512a. A person engaged in the business of, or acting in the capacity of, a person required to be licensed under this article, shall not maintain an action in a court of this state for the collection of compensation for the performance of an act or contract for which a license is required by this article without alleging and proving that the person was licensed under this article at the time of the performance of the act or contract.