Troubleshoot viewer and converter errors

Start with the exact visible error, file format and browser. Most failures come from memory limits, unsupported old chunks or uncommon compression.

01

What to do

  1. Reload once and retry with other large tabs closed.
  2. A very old pre-palette Java chunk or uncommon external/LZ4 region chunk may not convert.
  3. If the GPU renderer fails, lower the performance profile and disable expensive shader effects.
02

Privacy and reliability

Files are parsed on your device. In the viewer, the original is also kept in your private library after the storage notice and stays private until you publish it; the standalone converter never uploads anything.

TipKeep a backup of the original. Browser conversion is convenient, but it does not replace world backups or source control.
03

Continue learning

Return to the documentation hub, read the format guides, or open the 3D viewer with the example build.