get EVERY TIME the error "Failed to login: The authentification servers are currently down for maintenance."

Good Evening Mojang-Supporters,
As I mentioned above, the error "Failed to login: The authentification servers are currently down for maintenance." occures every time I want to join a normal Minecraft-Server and every time I want to login to the Technic-Launcher. I "googled" about thousand times but I found no solution. I only found people who told that the authentification.mojang.com server is offline when this error occures but I coded a tool to look up whether the Mojang server are offline or not and I also tried other tools but every tool told me that everything is ok. I also found people on the internet who have this problem with a cracked minecraft version but I bought my version of minecraft and I also can login to my minecraft account in the normal minecraft launcher and on minecraft.net and mojang.com. I'm very sorry for my bad english and I hope someone can help me. Thank you for having time to read my thread.