Error message Unreal engine -> Engine can not start

Hello there,

I left the pc yesterday night, before I had started downloading and installing unreal the new version.
Today afternoon it has looked like everthing is completed. Unfotunatly the pc was very slow. After severall restarts of the PC I started Unreal Engine 5.
The Engine trys to start but then I get an Errormessage.

It would be nice if someone would give me a helping hand.
Maybe the queastion should be asked in a other kathegorie?!?

Kind Regards

Hello there @Producer1980!

That is unfortunate, let’s try to resolve it. This error and scenario has been encountered a few times through the community, and two methods of resolution stand out:

Solution 1:

  • Open the \Engine\Config\BaseEngine.ini file
  • Search for the [Zen.AutoLaunch] category and after the “DataPath=” folder path use the old " %APPSETTINGSDIR%Zen/Data " format or any custom path access like “DataPath=%ENGINEDIR%Zen/Data
  • Test opening a new project
  • UE should open with no issues

Solution 2:

  • Modify the “BaseEngine.ini” file @ X:\Folder\Epic Games\UE_5.4\Engine\Config >>
Search for "[Zen]"
Change AutoLaunch=true to AutoLaunch=false
  • Manually launch “zenserver.exe” @ C:\Users[username]\AppData\Local\UnrealEngine\Common\Zen\Install
  • Launch UE5.4 exe
  • Click OK on the following windows
  • UE should open with no issues

If all else fails:

  • Perform a full uninstall/reinstall of all Epic software
  • First, uninstall the engine, launcher, asset packs, etc
  • Next, open the registry directory HKEY_CURRENT_USER\Software\Epic Games\Unreal Engine\Builds, and delete any build entries
  • Finally, delete the folders %userprofile%\AppData\Local\UnrealEngine and %userprofile%\AppData\Local\UnrealHeaderTool
  • After that, no elements related to UE should be left in your system
  • Now, reinstall UE launcher from scratch, and add any version of the engine you need