The Mac swears at you!
I think this could be worded in much more explecitive and redundant way, still giving away as little information as possible:
%@!!! The %@ preferences pane could not be removed because a %@ error occurred. Something apparently has gone %@ wrong. Expect that the %@ preferences pane is still there, because the removal attempt was interrupted by that %@ error. OK ??
P.S. Yeah I have nothing better to write :P