The challenge - Your Spouses Answer and Cross Petition

Your spouse can challenge the right of the court to proceed on the basis that you have not been in Missouri long enough for the court to give you assistance (90 days), or that your marriage was illegal, or that you lack the mental capacity to bring suit ( say trip to doctor).

However, your spouse can not deny receiving the papers because the service officer files an affidavit under oath regarding the service.

Many courts have lists of private individuals they deen reliable enough to serve papers. These folks charge a reasonable fee, and have more time than the overworked deputies to accomplish service.