Hi. Experiencing the same problem.
In my BitComet 1.38 (64bit), in the sign-in pane, I'm getting "Connecting to server..." for a few minutes and then "Unable to sign in CometID at this time". (See below.)
And on cometid.com, I can log in, but all my scores and ranks have disappeared. (See below.)
I know everything was fine about 6 hours ago. Not sure when exactly the problem began but it's been going on for at least an hour now.