Once a Judgment is entered, it is a complicated process to have it removed. Basically, if there is no evidence in the official court file that you were served with a copy of the Complaint which ultimately resulted in the Judgment, a Motion to the Court would probably do the trick. If there is such evidence, then the situation becomes far more involved. Check with a civil lawyer in your area for more precise information. Initial consultations are usually done at no cost - ask first. If you don't know any lawyers ask your friends and family. If they don't know any, go to http://www.nmbar.org/ and find one from the list there.