Like I said before I have changed oil for around 20 years, and I'm just 33 !! That being said I'm as prone, maybe even more so to mistakes than anyone else. I always check, and then double check to make sure the gasket is on the oil filter, and then a quick wipe around the oil filter mating surface with a paper towel just to make sure I don't feel anything stuck. I also pour a small amount of oil into/onto the top of the filter, then rub this oil around the gasket to saturate the gasket.
I'm a Machine Technician by trade, and also was/am a Chronic Technician (kinda one step above the machine tech) I always hand tighten the oil filter, and never had one leak. This oil filter was also on tight I checked when removing the filter. I have gone over in my head of the many things I could have done wrong to cause this, and none have shown up. There are two things that could have happened that I can think of, these are a faulty oil filter as I think is the most likely situation, or a piece of grit had gotten between the gasket, and mating surface. The second is highly unlikely as I think anything big enough to cause a problem would have shown up when I remove the filter, however I guess it could have dropped off, or even run out with the oil in the filter.
Oil was dripping from filter edge itself, and had been dripping enough to spot where I parked, and the car does not leak oil. I wiped the oil as mentioned in previous post at the rim of the filter, and almost immediately the oil reappeared in the form of a oil droplet which looked to come from the area of the gasket, however you can't really see exactly where the oil came from on the lip of filter, I just assumed the gasket area as the gasket is just a couple mm inside the lip/rim.
I can snap a picture, and I will (not tonight lol to cold) however the filter is flawless by looking at it, well with my eye anyway.
