So, I've been having issues all throughout today, I can't log into any tekkit, ftb, and hexxit servers. I'm saying these three specificially, because those are the ones I've tried. However, I can get on any minecraft server no problem. I have a legitimate account, so I'm quite sure that's not the problem. However, I'm not sure if this is the place to put this thread, or somewhere else. I'm not even sure if this is the right place to ask. Is anyone else having this issue? Is it just me?
Guys I had the same problem about the bad login thing so I went to work and found out how to fix it at the bottom right corner where is shows your account details press log out and log in again but press don't remember account and you will be able to play again yours truly damuto123456
Sky_Voux's solution is server-side. The server.properties file is (as the name suggests) a file which holds the server properties, one of which is online-mode.
Online-mode set to true means that the server will authenticate usernames through the Minecraft official servers.
Online-mode set to false means that the server doesn't check usernames with the official servers and just lets them in. This is very insecure for the server and allows people to login as the owner and change settings, grief etc.