If you are having problems logging in try this!

[ntall1]

This worked for me, so thought I would share and hopefully help someone else get on.
Use these steps:
-close client
-open command prompt
-type: ipconfig /release
-press enter
-type: ipconfig /renew
-press enter
-type: ipconfig /flushdns
-press enter
-open client
-have fun

Hope this helps someone.

Simply restart your router. That is what I have been doing it and it works every time.

For some reason, after logging out of the game, the game retains a connection to your system. To break that connection you can simply restart your router. Release/Renew/FlushDNS might work for some that are not behind routers, but restarting the router has worked every time for me.