a problem with NUnit environment

I have a problem: if i run this test in NUnit ,it works

Board  board = new Board("ab", 12, 120,BoardType.OEM, BoardSide.DoubleSide);
Assert.NotNull(board);

but when i want to开发者_C百科 add another Assert statement as

Assert.AreEqual(board.SNR, "ab"); 

it runs, and the NUnit window is immediately closed. Why does it close automaticaly?

Stackoverflow? (no pun intended)

Seriously, have you tried to trace into board.SNR?
A stackoverflow might explain the closing of your NUnit window.