KSP Sometimes space bar or staging dosen't work

[kangaroo3505]

Every 40 hours of playing ksp in irl time space bar dosen't work but if you restart the game it does?

[fleventeen]

It is probably healthy to take a break after 40 hours anyways. 

But seriously, do you have a particular need to keep the game open that long? I saw your other question regarding corrupted thumbnails, it is possible that my suggestion there will help this. Also keep in mind that games can get a little janky if left open too long.