Problem:
Getting stuck at 'Connecting' and then getting an 'unable to connect, please try later' message.
Reference:
http://forums.wow-europe.com/thread.html?topicId=11030834222&sid=1&pageNo=1
Solution: (for me at least)
Close the game.
Open a DOS window and type
ipconfig /flushdns
This solved it for me and I logged in first time after I had done this.
I use that about once a month just to keep it all fresh...I find with my isp it is needed!