Everything has to be conduit by code. When i use my stop shock tester everything in the house shows no problems which is two wired. However, when those wires run from the panel box to the detached garage, it shows bad ground. When i use two other testers that doesnt contain bad ground, it shows correct. The new receptacles and wiring i checked a half dozen times to the electrical outlets which is wired 100 percent correctly. Also to note before changing receptacles, the old receptacles also showed bad ground. Why the discrepancy between the house and the detached garage? Thank you again in advance.