Unity 2018升级至2019.3后Vuforia兼容异常问题求助

Hey there, I’ve dealt with this exact migration headache before—moving a Unity 2018 project with Vuforia 8 to Unity 2019 and updating to Vuforia 9 often leaves leftover files or broken references that cause issues. Here’s a step-by-step breakdown of the fixes that usually resolve this:

• Completely purge old Vuforia 8 files first
  Half the battle is cleaning up leftover Vuforia 8 assets that conflict with Vuforia 9:

  1. Open Window > Package Manager, locate the Vuforia AR package, and uninstall it.
  2. Navigate to your project’s Assets folder and delete any remaining Vuforia directories or stray Vuforia-related files.
  3. Head to Project Settings > Player > Other Settings and remove any Vuforia-specific entries from the Scripting Define Symbols field.
  4. Restart Unity to ensure all old cached files are cleared.

• Install Vuforia 9 properly for Unity 2019
  Unity 2019 uses the Package Manager for Vuforia, but a manual git install often avoids version mismatches:

  1. In the Package Manager, click the + icon in the top-left, select Add package from git URL, and paste com.ptc.vuforia.engine—this pulls the latest Vuforia 9 version compatible with Unity 2019.
  2. Once installed, open Window > Vuforia Configuration to confirm the setup, and double-check that your Vuforia license key is correctly entered (old keys can fail after version jumps).

• Repair broken scene and prefab references
  Vuforia 9 made subtle changes to component namespaces and assemblies, which breaks old references:

  1. Open each scene with AR content, select your Image Targets and AR objects, and check the Inspector for missing or broken scripts.
  2. If you see "Missing Script" errors, reassign the updated Vuforia 9 scripts (most class names like ImageTargetBehaviour are the same, but they’re now in the Vuforia assembly).
  3. For prefabs, right-click the prefab in the Project window, select Select Prefab Instance, then use Revert or Apply to sync the prefab with the new component versions.

• Update Unity 2019 player settings for Vuforia
  Unity 2019 has key settings that Vuforia 9 requires:

  1. Go to Project Settings > Player > Other Settings and set Scripting Runtime Version to .NET 4.x Equivalent—Vuforia 9 doesn’t work well with the older runtime.
  2. Enable Vuforia Augmented Reality Support under XR Settings (this is where Unity 2019 manages AR providers).
  3. For mobile builds, confirm your minimum API level meets Vuforia 9’s requirements: Android needs API level 21+, iOS needs iOS 11+.

• Check platform-specific build configurations
  Sometimes issues are isolated to Android or iOS:

  • Android: Verify your Android SDK and NDK versions in Edit > Preferences > External Tools match Vuforia 9’s recommendations (Unity 2019 works best with SDK 29+ and NDK r21b).
  • iOS: Ensure you’re using an Xcode version compatible with Unity 2019, and reimport Vuforia assets via the Package Manager if you see iOS build errors.

If all else fails, create a fresh Unity 2019 project, install Vuforia 9, then manually import your assets and scenes one by one. This helps identify if the problem comes from corrupted project meta files or leftover settings.

内容的提问来源于stack exchange，提问作者Tom