Not using the same version as the server.

[Notsuchabadguy]

I just updated Terraria, and now that little message pops up every time I want to log in. Is the server getting an update? Or am I just doing something wrong?

Thank you, and sorry for the annoyance.

[Dungeon_Lord]

I can't even use terraria it keeps saying crap about can't play terraria right now...

[Haagon]

yah same thing for me too it wont let me on the server cuz of that message, isnt it updated yet?

[JRParadox]

The reason that the server is not up is that T-shock is not updated yet and it is too risky to update and run the server without the mod. In case you do not know T-shock is a Terraria mod which most servers use and have which basically adds some minor features such as the ability to use warps, spawn mobs, spawn items but what it more importantly does is prevent griefing by auto-kicking and banning people who use explosives.