Having difficulty connecting to servers

[shadowofdeath]

I was playing like ten minutes ago and i was fine then i just froze in mid air so i left and tried to join the same server and then this poped up

Any idea what is causing this ?
BTW it only happens when i connect to servers with players it

 

[Siantlark]

Same problem.

 

[GReaper]

Auth server needed a restart, thread closed.

 

[shadowofdeath]

Thank you