Immediately upon the entry of an order or judgment, the clerk shall serve a notice of the entry by mail in the manner provided for in Rule 43.01 upon each party who is not in default for failure to appear and who was not present in court in person or by attorney at the time of the entry of such order or judgment. If such notice is not given, the order or judgment shall be set aside for good cause shown upon written motion filed within six months from the entry of the order or judgment. This Rule 74.03 shall not preclude relief under Rule 74.06.
Mo. R. Civ. P. 74.03