corrupted saves in 1.58

I just tried to load the save for a game I've been playing for awhile 1.58, BM 1.11(game was started in BM 1.10),so it lags during loading, then I get a white screen with music and this message "cannot create file c:\program files\strategy first malfador machinations\space empires V\temp_1.dat". I've loaded it many times before without problems, what happened?