Perhaps the internal battery (usually 9 V) is either dead or not making good contact. The resistance measurement depends on using juice from the meter's own battery. When you are on the "ohms" setting, with leads plugged in to meter, just briefly touch the neg and pos probes together. You should see a swing from infinite (probes not touching) to 0 (probes touching), if the internal battery and all the settings and connections are correct. (Also, is it possible to take it back to where you bought it and ask for help? Could be a defective unit.) -- LC