Packaging UE, DoesPackageExist errors

Hi, I am trying to package a project that uses cesium in Unreal Editor 4.27, build using VS2019, and using the v1.5.1-plus-4.27-support branch from github. I am able to build my project fine, but when I go to package for a Windows 64, I get many of the following errors:

UATHelper: Packaging (Windows (64-bit)): LogTemp: Warning: C:/Users/xxx/MyProject/xxx-20495/Plugins/xPlugin

PackagingResults: Warning: C:/Users/xxx/MyProject/xxx-20495/Plugins/xPlugin

UATHelper: Packaging (Windows (64-bit)): LogPackageName: Error: DoesPackageExist: DoesPackageExist FAILED: ‘/CesiumForUnreal/CesiumCreditSystemBP’ is not a standard unreal filename or a long path name. Reason: Path does not start with a valid root. Path must begin with: ‘/Engine/’, ‘/Game/’, ‘/Paper2D/’, ‘/AnimationSharing/’, ‘/DatasmithContent/’, '/Geomet

ryMode/’, ‘/Niagara/’, ‘/SpeedTreeImporter/’, ‘/MediaCompositing/’, ‘/MagicLeap/’, ‘/MagicLeapPassableWorld/’, ‘/AudioSynesthesia/’, ‘/OpenXR/’, ‘/OpenXREyeTracker/’, ‘/OpenXRHandTracking/’, ‘/PostSplashScreen/’, ‘/SunPosition/’, ‘/Synthesis/’, ‘/WebBrowserWidget/’, ‘/Takes/’, ‘/ChaosNiagara/’, '/Chstrong textaosClothEditor/’, ‘/ChaosSolverPlugin/’, '/GeometryCollectio

nPlugin/’, ‘/GeometryProcessing/’, ‘/Landmass/’, ‘/MotoSynth/’, ‘/Water/’, ‘/PythonScriptPlugin/’, ‘/OculusVR/’, ‘/SteamVR/’, ‘/Config/’, ‘/Script/’, ‘/Extra/’, ‘/Memory/’, or '/Temp/'

I am able to find the CesiumCreditSystemBP asset in file explorer, as well as the others. If anyone could tell me what it is looking for here, that would be a big help!

Hi @fullerar,

We just published an official build for 4.27 to the Epic Marketplace. I suggest you try that, as I’m not sure what state the v1.5.1-plus-4.27-support branch is in.


Hi Kevin, thanks for the suggestion. I have the 4.27 installed, but when I go to install Cesium from the marketplace, it says no compatible engines are installed? I do see on the Cesium page that it says compatible with 4.26-4.27

I had the same problem at first, but it was fixed by closing and reopening the Epic Launcher.