A couple years ago, my sister and I wanted to play on a LAN world. It usually worked, but this time it didn't. Yes, we are on the same IP. Yes, both of our javaw.exes' are allowed through the windows firewall. So then we tried connecting to her world, but it still didn't work. So then I look some stuff up. None of it worked. And here I am, 3-4 years later. Posting about it on minecraft forums. Something made me think our non-windows firewall was blocking the connection, so I tried allowing it access through. Guess what? Still doesn't show up. The games haven't showed up for a while. Yes, both of us have even tried reinstalling minecraft, I've even tried starting a server and, to no suprise, NONE of that works. I have little to no clue what's going on, and when I think I know the answer things just end up getting worse. The only way we can play together is through Win10, and that version is quite bad. We've been looking this up for years now, and the answer is still unclear.