WOTLK log in - Could not log into World of Warcraft at this time....

I get the error message "Could not log into World of Warcraft at this time. Please try again later."

Tried viewing some old threads and trying out what people said worked - moving the folder, deleting/re-adding the addons folder etc. Got nothing so far.

Update: The problem has resolved itself. I didn't do anything, just came back after doing some washing and it logged in no problem. Cause for both problem and resolution remains unknown to me.