Minecraft wiki entry for Crash, associated text: Crashes can easily occur due to mod conflicts, wrong versions of mods (for example, many of the 1.7.10 mods are not compatible in Java Edition 1.13 due to the data values conflicts due to the Flattening, but almost all mods for Java Edition 1.16.2, 1.16.3 and 1.16.4 can run on Java Edition 1.16.5, as Java Edition 1.16.3 and 1.16.5 are minor updates with just minor fixes), or buggy mods (particularly among Fabric mods). If the player has installed several mods, if using the older launcher, they should try renaming the "bin" directory in the Minecraft folder, then start Minecraft (Or replace the current minecraft.jar with a clean minecraft.jar from either a clean backup, download a jar file from the internet or force update the game should cause the player to get a new clean jar file.). A new bin folder is created. The player should remove the problematic mod. Now, the player should install each mod they desire one at a time, starting Minecraft and assuring that there is no crashing for each mod. Once the crashing starts occurring again, the last mod installed is likely the problem, or another mod simply does not work with it. Either way, the player should either remove the mod they determined to be causing problems, or repeat the first step, except without installing the problematic mod.