Range Check Error. They occur when some value goes out of the operable range, such as more than 255 standard movement points from components on a ship hull (this no longer causes a RCE, but it used to be a major headache).
What Fyron said. Nothing could make you boil faster than playing 101 turns of a game just to have it RCE out. Most cases it was just replay the turn as the AI player and find the HANG issue. It was mostly the AI trying to retrofit an old design that it was unable to do. Or launch to many fighters at one time.
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Creator of the Star Trek Mod - AST Mod - 78 Ship Sets - Conquest Mod - Atrocities Star Wars Mod - Galaxy Reborn Mod - and Subterfuge Mod.