When did Hitler lose the chance to win the war?

When did Adolf Hitler lose the chance to win world war 2 ? What was the moment in time that before it he could still possibly win the war, and after it his defeat was a matter of time ? (and long continued fighting that still cost so many lives). When was it? How early or late was it ? How about starting from a relatively late date, when we're sure that Hitler's defeat was just a matter of …

…people with no other choice but to fight their toughest war, and utilize their endless resources much better than ever, and by doing so Hitler lost his last remaining options and his chance of winning the war. So in December of 1941, at the gates of Moscow, Hitler's war was lost. It took 3 1/2 more years to end, thanks to the outstanding fighting skill and loyalty of the german soldier, but he could no longer win it.