If you are playing a campaign and have gotten past scenario 1 you might run into a situation where you can't open a saved campaign game.
1) Play and win Scenario 1
2) Save game at first Save Game prompt
3) Start Scenario 2 repair, upgrade, add core, purchase secondary, deploy, start turn for Scenario 2.
4) Do something incredibly stupid like charge APC carrying A0 into waiting enemy MBT and watch them die.
5) Decide that you are in fact too drunk
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and try to restart the game by choosing End Game.
6) Attempt to open the saved game doesn't work. Slight screen "blink" but the save from the end of Scenario 1 doesn't load.
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7) If you QTD and reopen MBT everything works fine and you can open the "End of Scenario 1 Save".