I can't log onto servers

From what i've read this is actually because A LOT of servers are purely fake, taken down, full or under construction, It seems that there is a real issue of servers just being down completely,

I dont think this is a technical issue on your end, it is just significantly harder to find a server that is actually on, Try joining a server that maybe your friends are in and is not full,

If you are on android you can also try clearing the data of the minecraft app which results in the app reverting to a "Fresh" version,

Check that your screen name doesn't use any strange characters.

My sons both have a Galaxy tab. While one of them could connect to the Lifeboat Server instantly, the other could not. It was rather frustrating, and an answer was nowhere to be found, an answer that solved the problem that is. So we installed MCPE on my Galaxy tab as well, and tried to connect to the server. It worked in an instant.

So why would two tabs work just fine, while the third one wouldn't? In our case it was my son's screen name that would not allow him to connect to the world. To make sure we were on the right track we changed the screen names on all three tabs, and BINGO, it was the screen name indeed. My son now has a new name, and with that he can connect.

This question is from 2014, but I will answer from my experience in mid-2020.

There are 2 reasons why this could be possible:

1. The server might have certain bugs and issues still not fixed or mismanaged leading to a bad experience logging in to a server. This happened to me in Lifeboat.
2. You have a high ping. In my sorts, playing a game with 300+ ping could be a buggy experience especially logging in to servers. Using ping less than 150 is suitable.