Is it voltage on a ground wire - green or bare copper - or on the white “neutral” wire. Voltage on a ground wire is asking for a lot of trouble and it’s amazing anything actually works. The white wire is “ok” except that it is backwards and therefore unsafe. It should be the black wire that is HV and the white wire should be grounded, though it is not a ground wire.
Also, get one of those little voltage detecting “pens” that beep and lights up when you touch it to a HV wire. First make sure it works by touching it to a live wire and then check everything around the circuit, outlet box etc. that is supposed to be “dead” to make sure it is really dead. And then check it again to make sure it is working. And check with a voltmeter as well. The advantage of the pens is that they will go off even when you cannot reach all the wire nuts or when you think everything is dead, but it turns out that there is another circuit coming into a box (multi-floor light switches in staircases are a huge problem this way)
The voltage detecting pen didn’t pick up on the 25 VAC on the line, hence my zot.
When I put my meter to work, I got 110 VAC ground to neutral and 120 VAC ground to ground, but this was specifically only on this circuit. When testing the ground block and neutral blocks in the breaker box, there was no current, which lead me to question the switch. The voltage is confined to the downstream from the switch. This still isn’t okay, but it’s less drama than if the entire house had current on ground, which it does not.