This question already has an answer here:
I have hosted Minecraft servers from time to time; I know how to do it.
Now suddenly people can't seem to join my server. I am talking about a LAN server now because I need to port forward if I want people from all over the world to join me. Before, everyone on my internet could join me. I used Hamachi so my friends could join me from their homes sometimes, too. Now people can't seem to join me, but I can join their servers.
This happened about 1-2 weeks ago now.
Can anyone please tell me either what is wrong or how to fix this problem? I would be so greatful if anyone could.