Every time I try to log in in the launcher, I get an error message saying:
Sorry, but we couldn't connect to our servers.
Please make sure that you are online and that Minecraft is not blocked.
(SocketTimeoutExpection: connect timed out)
My internet connection works.
Best Answer
It's possible that the Mojang Authentification servers were just down for a bit. You can check the status of the servers on https://help.mojang.com/ or http://xpaw.ru/mcstatus/. https://twitter.com/MojangStatus might also be of helpful to check. If the servers are down, there is nothing you can do on your end, and it's up to Mojang to fix it.
If the problem persists even when the servers are up, make sure Minecraft is not blocked by any firewalls. On Windows, you'll need to allow both
java.exeandjavaw.exe. I suggest deactivating your firewall for just a few seconds to check if that is indeed the problem before trying to fix stuff that is not broken.