Hi there, in order to prevent early failure of my electronics and for peace of mind, I'd like to identify and correct miswirings in my appartment's outlets. No law requires anyone to do anything about it. First things first: my budget is exactly 0$ for this repairs, and no, my landlord won't correct anything unless an unfortunate event forces him to do so, so don't ask. I do have: a digital multimeter, common 3-prong 120V outlets. I still don't know: even with 3-prong, the "earth" may be unconnected. The building is from the 50s and its electrical system was not upgraded, and ungrounded outlets were common back then. I measured: 112V between neutral and line (normal), but about 47V between neutral and ground, and around 66V line-to-ground. It would normally mean than ground and neutral are reversed, but from looking at the wiring from one plug, there's no wire connected to the green screw, meaning it's ungrounded. What else would cause the "ground" to be almost half the potential of the line? How would I find the exact faulty outlets?