Note: Always make backups anytime you are modifying any game files!
On occasion, Minecraft can encounter an issue that will corrupt the save data of a World save. When this happens, the chunks in game can be reset to how they were when the world was generated or disappear completely. Many factors can cause corruption and, in some cases, can prevent the world from being opened at all. However not all hope is lost if a world save is corrupted.
The process to fix a corrupt world can be a bit challenging and is not guaranteed to fix the world every time. Making frequent backups of your world will always be the best and safest way to ensure you can recover from a corrupt save file. Always make a backup before you attempt this process even if your world has already been corrupted.
Since this process involves transferring and modifying files on your system, support is not able to assist with this issue. However, there is a guide available on the Minecraft Wiki to help walk you through the steps. Since support cannot guarantee this process to work please use it at your own risk. To continue to the guide click here.
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