A lot of people (the majority tbh) reporting this problem are suffering a timeout issue - their computer isn't recieving/sending information quickly enough so they don't connect when trying.
The cure? Keep trying. Some people have success using the /join server command, others just keep trying to connect until they're on.
<Erf> SkulFuk: gf just made a toilet sniffing joke at me
<Erf> i think
<Erf> i think i hate you
Basically, there are belt restrictions on static servers. If you can't connect but you can create servers, it just means that your belt is too high or low.
|11:33| »» [shark] so you're saying that you just paid 80 euros for pussy
|11:33| »» [Quit] [x] shark [[email protected]] [Quit:]