Mich. Comp. Laws § 211.431
After the expiration of 6 months from and after the time when any deed made to the state under the provisions of section 127 or section 67a of Act 206 of the Public Acts of 1893, being the general tax law, and acts amendatory thereto, shall have been recorded in the office of the register of deeds for the county in which the land so deeded shall be situated, the title of the state in and to the same shall be deemed to be absolute and complete, and no suit or proceeding shall thereafter be instituted by any person claiming through the original or government title to set aside, vacate or annul the said deed or the title derived thereunder: Provided, That as to all lands heretofore deeded to the state under the provisions of said section 67a of said Act 206 of the Public Acts of 1893, the title of the state thereto shall be deemed to be absolute and complete after a period of 6 months from the taking effect of this act, and no suit or proceeding shall thereafter be instituted by any person claiming through the original or government title to set aside, vacate or annul said deed or deeds or the title derived thereunder.
MCL 211.431