Happened to me the first time I cubed. Next time I filled to the brim with hot wort then capped then turned over so the hot wort heat sanitized the handle and lid, never had a prob since. I rescued the original by calling it a wild yeast sour, quite drinkable too.
I've just spent a whole evening reading this thread from start to finish. Learnt a lot and been inspired to hit up a school nite brew. Thank you all for your passionate input and knowledge.
You guys rock,!