From my understanding an issue sometimes accrues when the game isn't properly shutdown and causes some bugs with showing the world in the list, it may happen due to: game crashes, power shortages, sudden restarts, and sometimes from other reasons.

The game and files are still there but are hidden in the "Start Game" worlds list.

This fix is basically making a new game or empty folder where the game saves are saved and copying the backup into that folder.

0.Launch the game and do not quit the game until told to, the cloud changes stuff and makes it revert back if done while the game is off.

1.Create a New World


2.After the world has loaded and you're in the game, quit back to the worlds list

3.Open the World file location from the world menu

It will Open the folder of the new world you created, this will be the place where you put your backup files into.

4.Delete "Players" "Level" "LevelMeta" and "LevelData" from this folder.


5.Locate the other world save, it should be right outside of the new world folder we just cleared, and it should contain the same amount of files as we just saw (looking and modified time helps).



Optional - You can copy the "WorldOption.sav" file that is inside of the old world you want to recover into the new world folder that we cleared to import the world options.

6.Go into the backup folder of the save you want to recover the files from, there should be "local" and "World",




7.Open "local" folder and open the Latest created/Modified folder (the last saved backup tend to be corrupted and you should use an earlier one), then Copy "LocalData" into the new world folder that we cleared.





8.Now Go back To the "world" folder and open it, Open the folder of the same creation/modification date that you copied from in step 7, then Copy "Players" "Level" and "LevelMeta" into the new world folder that we cleared.



9.Inside the game, go back to the main menu (Must), into "Start Game" where you see all the world lists (makes it refresh the world lists when we leave the menu and come back into), the new world should be named differently as well as days and level should be different.

10.Quit the game, so the cloud will save the changes.

11.Launch the game and play.

12.if there are errors/bugs/prompted to character creation or other players on your world have those problems, use an earlier backup or try the notes below.

Important Notes:

• You can rename the world folders to make it readable instead of it being a long line of letters & numbers
  
  
• I haven't confirmed that if you imported from an old world into a new one and renamed the new one, it may result in future backups of this word be created in the old world instead of where its supposed to be which is the new one (if you have noticed so, please tell me).
  
  
• for world saves with more then 1 player:
  player files can become corrupted prior to doing this fix and you will know if your player save is valid or not if you will load with your character or asked to create a new one, you can try to import the specific player save from an older backup and hope that at least one backup has a working version of your player save (The host player save is always "00000000000000000000000000000001.sav").
  
  
• lost map progress
  if lost map progress you can copy and paste a different "LocalData" file into your world, they are in the backup folder -> local folder (see step 7 for reference).
  On multiplayer worlds you want to do the same (worlds you joined only contain "LocalData" and backup folder).

Same Idea as what I found but explained diffrently : https://steamproxy.net/sharedfiles/filedetails/?id=3143830517

Reddit Post For a different approach:
https://www.reddit.com/r/Palworld/comments/19bbkru/guide_restoring_a_corrupted_save/

This was made by following the instructions from here : https://www.reddit.com/r/Palworld/comments/19b7vqr/move_save_data_from_gamepass_to_steam/


1.Download "xgp-save-extractor.exe" from https://github.com/Z1ni/XGP-save-extractor/releases/tag/release-2024-02-01 (Might need to wait to be updated because of constent updates of the game)


2.Open it, it will extract saves from every game pass game supported to the same folder you opened "xgp-save-extractor.exe" in (I don't know if there is a way to extract only palworld saves and exclude other games, so if you have many games it could take awhile), we only need the palworld saves.

3.Launch palworld, and keep it open.

4.Create a New World ( Only if you haven't created a world before in steam).


5.After the world has loaded and you're in the game, quit back to the worlds list ( skip if you skipped step 4).

6.Open the World file location from the world menu (any world will do)


7.Locate where the game saves are stored in the steam version, It should be outside of the folder it led to in step 6.


8.Move all the the saved games that are in the extracted palword saves we got into the folder in step 7.

9.Go back to the game and click on "start game" there should be extra worlds that we imported.

10.Restart the game (we restart so the cloud saves those changes).

11.Launch the game and play your world.

• Severe crash episodes upon playing
  
  Once inside game everything was running smoothly, there was very little lag and FPS drop that might lead me to believe my issue was connection or spec related. After about 5-20 minutes of gameplay which included gathering, building, location checkpoints and multiple saves [auto and me manually exiting to menu] my game would simply crash to desktop. There was no "report crashes/bugs" screen as I was seeing before during the mass crashes and data drain.
  
  
  
• Map data leak
  
  After a crash any progress made on the map vanished. Things such as teleports/bosses/items that I collected were not regenerated and remained in my possession but I simply couldn't see it on the map due to it being blacked out as though I had not covered the area. Every crash I logged back into the same location I crashed, on the map it appears as a silhouette around my "player" icon with everything else blacked out.

1.Close out of the application completely.

2.Open Steam<Tab to Palworld [do not hit play]

3.Click on the Settings Gear on the right side [next to information button]


4.Click on "Properties"


5.Click on the category "Installed Files" and then "Browse"


6.Open "Palworld.exe" from this folder (you can make a shortcut of it).


This actually fixed my issues immediately

I recommend using https://haruhost.com/ to host dedicated servers on your pc.

Tutorial on how to set it up : https://www.youtube.com/watch?v=nbSdr5i4Xss

You can also try Paldeck Enhanced[www.overwolf.com] on the overwolf app to have useful overlays in the game.

If you need more help, my discord is "_l_o_o_p_", i'l help you when I'm online.