You must take a look in the claymore thread, there are a lot of post since more than two weeks ago dicussing that problems with unimining an other XVG b2s pools.
I also have this problems and tried almos all the XVG pools.

Tired of trying XVG pools i started mining XSH b2s in antmine pool and im geting 45xsh/day aprox with 9200Mh/s that is better than keep trying pools every day.