LAN Issue

I have 3 computers that I've been able to open to any active LAN World simultaneously.

Recently, when starting a LAN World, no LAN Worlds can be found on the other computers. I haven't changed any hardware or network settings. I've tried connecting direct using my IP address without success. I've also tried connecting to the game-generated port number with the same negative results.

Reverting to a previous release also yielded no positive results.

My daughters and I can now only play on separate "worlds" which takes most of the fun away from playing the game.

Has anyone else experienced this issue? Does anyone know a fix for this?