Well, I've been working on a map for quite some time and when I tried loading it up today, I got this message. This is ridiculous because there clearly is a missiongroup in my .mis. I've spend hours comparing my .mis to other maps, and I can't see why it doesn't work, especially because it was working a few days ago. I'll post my .mis here, it would be great if someone could figure out why it isn't working. Thanks in advance. ---EDIT--- I managed to fix the issue. For some reason the precipitation was causing this error. After removing the lines of code involving precipitation, the map loaded like normal. I'm not sure if all precipitation will do this or if there was something wrong with the code.