Full crash while saving or playing

After loading a world, after approximately 1 minute has gone by, the game will pop up with a message that says "an error has one" and close the application. 

When attempting to save, it will say "generating world" and will either crash with the same error message, or will save properly.

This happens on personal realms and personal worlds. I was not able to get a screen shot because it didn't work when the application closed.