Seems to be an issue with the new US Pools, specifically US-East (didn't test West). BFGminer won't connect.

The command prompt goes to black and after a few seconds BFGminer says press any key exit and that it will try again in 15s (paraphrased).

At first I hadn't changed over to the us-east (still using the old us.multipool). But still does it, after making the correction.

The EU pool works, though.