225 ILCS 655/5

Each non-resident applicant for registration shall file with the Department an irrevocable consent that actions against the applicant may be filed in the circuit court of the county where the plaintiff resides or where some part of the transaction occurred out of which the alleged cause of action arose and that process in any action may be served on the applicant by leaving 2 copies thereof with the Director. Such consent shall stipulate that such service of process is valid for all purposes. The Director shall promptly forward, by certified mail, one copy of such process to the applicant at the address shown on the records of the Department. No foreign corporation shall be registered under this Act until it has been authorized by the Secretary of State to do business in this State.