First things first: your save probably isn’t broken

When you see “World not found” / “can’t find save,” don’t assume your world is gone. In the vast majority of cases this message means the archive’s folder structure is wrong: the game finds a world’s entry point through the level.dat at the root of the archive. As soon as level.dat isn’t at the root of the archive, or the world is wrapped in an extra folder, the game follows the root, fails to find the entry point, and reports “World not found.”

In other words, the world data inside the file is often still there—it’s just that the way it’s packaged makes the game unable to recognize it. So the first step isn’t to re-import over and over or reinstall the game, but to confirm exactly where the problem is.

How to pinpoint and fix it: free on-device diagnosis + simple structure repair

Open the problematic .mcworld or .zip in TopoBlocks to diagnose it. The diagnosis runs on-device by default and is free. It checks the file type, version, and folder structure, plus whether any key files are missing, and tells you directly whether level.dat is at the root and whether there’s an extra folder wrapped around the world.

  • If it’s a folder-structure problem—for example level.dat buried in a subfolder, or the world wrapped in an extra outer directory—this kind of simple structure repair is free. It moves the files back to the correct level and generates a new .mcworld that imports normally.
  • It never overwrites your original file. This is a product red line: a repair always generates a new version. Your original file and its hash are preserved and traceable, so there’s no “fixed it wrong and can’t go back.”

For the most common cause—“an extra folder wrapped around it”—see A nested folder is keeping your world from opening. For a systematic look at the full diagnose-and-repair flow, see the in-depth tutorial Import and Repair.

If it’s not a structure issue: an honest note on the limits

Simple structure repair only fixes file / packaging / folder-level problems. If the on-device diagnosis finds not a misplaced layer but deeper file corruption, you can use Advanced Repair (¥9 per fix). Before you pay, you’ll see the specific problem, the success probability, the risks, and the refund rules. Prices are shown in the app, and failed repairs are refunded automatically, so you’re never paying blind.

One more honest reminder: some “can’t get in” cases aren’t file problems at all—for example, an incompatible game version, not enough device storage, or an installed mod that doesn’t match. These are outside the scope of structure repair, and structure repair won’t pretend it can solve them; you’ll need to troubleshoot them separately in the right direction. For a more general way to figure out why a world won’t open, see How to troubleshoot a world that won’t open. If you get an “import failed” message during import, see What to do when a world fails to import.