Editor

Bypass Engine Package Version Compatibility Checks

Unreal refuses to open assets saved with a different engine version by default. Two console variables in DefaultEngine.ini disable these checks, letting you open and inspect assets across engine versions without a full migration.

engine-versionpackagecompatibilityassetsini

QA workflows often require opening assets from a different engine version: comparing behavior across versions, investigating a regression, or opening a saved level from a branch you just synced. The compatibility block gets in the way.

The Fix

Add these two lines to your project's DefaultEngine.ini under [ConsoleVariables]:

ini
[ConsoleVariables]
s.EnforcePackageCompatibleVersionCheck=0
s.DisablePackageCompatibleCustomVersionCheck=1

What Each Variable Does

  • s.EnforcePackageCompatibleVersionCheck=0: disables the top-level engine version gate
  • s.DisablePackageCompatibleCustomVersionCheck=1: disables the custom version tag check inside individual packages
Warning: Opening cross-version assets can corrupt them if you save. Use this for read-only inspection only, and revert any accidental saves.

Alternative: Asset Downgrade Tool

For a more targeted approach that does not require ini changes, the community tool at 1danielcoelho.github.io/downgrade-unreal-asset can strip the version metadata from individual .uasset files.

Typical Use Cases

  • Opening a level from a newer engine build to inspect a regression
  • Reviewing asset content from a different branch without a full sync
  • Quick compatibility check before committing to a version migration