Error message: Save file was corrupt. A new save file will be created for you

I send my condolences out to you. Corrupt save files are the worst kind of glitch. I once had 150+ hours into TES: Oblivion and was hours from completing it when I got the corrupt save file error message.....on all 10 of my save files!!!!!!! I almost made
the evening news that night.

What external things would corrupt it then

How do I fix a "saved game corrupted" error?

You may get an error message that resembles the following when you try to play a saved game on your Xbox console: Saved game corrupted To resolve this issue, try the following solutions: Solution 1: Delete the corrupted game
file OR If you tried to delete the corrupted game file, and it doesn't work, your console may need to be repaired. Start the repair process. Note You cannot recover a corrupted saved game file. To protect other content, you must delete the corrupted file.
Determine if the saved game is corrupted. To do this, follow these steps: Select settings, System, and then Storage. Select the storage location, and then press the A button. Select Games and Apps, and then press the A button. Select the game, and then press
the A button. Select the saved game, and then press the A button. Note A corrupted saved game file is marked with a yellow exclamation point. If the saved game file is corrupted, delete the corrupted file. To do this, select Delete.
Learn more

It looks like maybe your save is corrupted.

Try to create a new save file or a new profile to test if the problem continues.

if the game works correctly on the new profile, then for sure your save got corrupted.

Solutions

To resolve this issue, try the following solutions:

Solution 1: Delete the corrupted game file

If the saved game file is corrupted, delete it. Here's how.

Note You cannot recover a corrupted saved game file. To protect other content, you must delete the corrupted file.

1. Determine if the saved game is corrupted. To do this, follow these steps:
   1. Select settings, System, and then Storage.
      
   2. Select the storage location, and then press the A button.
   3. Select Games and Apps, and then press the A button.
      
   4. Select the game, and then press the A button.
   5. Select the saved game, and then press the A button.
      Note A corrupted saved game file is marked with a yellow exclamation point.
      
2. If the saved game file is corrupted, delete the corrupted file. To do this, select
   Delete.

Solution 2: Request a repair

If the issue is not resolved, your console may need to be repaired.
Start the repair process.

More Information

This problem rarely happens. When you try to play a saved game file that’s corrupted, you may get an error message depending on how the game saves corrupted files. Some games just filter out corrupted content, but other games display an error message.

Access Application Data\.minecraft\saves. ...

1. Make a copy of the corrupted world folder & all files & folders inside, and rename it however you please. ...
2. Start Minecraft and create a new world, then save and close Minecraft. ...
3. Go back to Application Data\. ...
4. Cut the files (but not the folders) from the new saved world folder.
5. how-to-recover-corrupted-saved-world