Introduction
When working with Unreal Engine 5 (UE5) plugins, you may encounter the following error during project startup:
“Plugin ‘X’ failed to load because module ‘Y’ could not be loaded. There may be an operating system error, or the module may not be properly set up.”
This error typically appears midway through launching the Unreal Editor and can prevent the plugin from loading correctly.
Common Causes of the "Failed to Load" Error
The most frequent reason for this issue is missing plugin dependencies in the .uplugin file. If Module ‘Y’ relies on another plugin that hasn’t been declared as a dependency, Unreal Engine fails to resolve the required modules, leading to the error.
A common example is missing dependencies for Metasound, Niagara, or other engine-provided modules.
Checking for Dependency Errors in UnrealVersionSelector Log
To confirm whether your plugin has a missing dependency, check the UnrealVersionSelector log for warnings like:
Warning: Plugin 'X' does not list plugin 'Metasound' as a dependency, but module 'Y' depends on module 'MetasoundEngine'
This message indicates that Module ‘Y’ requires MetasoundEngine, but the plugin doesn’t declare Metasound as a dependency.
How to Fix: Add Missing Dependencies in .uplugin File
To resolve this issue, you need to explicitly declare the missing dependencies inside the .uplugin file.
Steps to Fix the Issue:
- Open your
X.upluginfile in a text editor. - Locate the
"Modules"section. - Add the missing dependency inside the
"Plugins"array.
For example, if Metasound is missing, update your .uplugin file like this:
{
"Name": "Metasound",
"Enabled": true
}
If your plugin depends on multiple missing modules, ensure that all required plugins are listed in the .uplugin file.
Additional Troubleshooting Steps
If the issue persists after adding dependencies, consider these additional checks:
- Ensure Plugin Modules Are Built: Run
GenerateProjectFiles.batand rebuild the project in Visual Studio. - Check for Operating System Restrictions: Ensure UE5 has the necessary permissions to load the plugin files.
- Verify Engine Version Compatibility: Some modules may require specific Unreal Engine versions.
Conclusion
The “Plugin ‘X’ failed to load because module ‘Y’ could not be loaded” error is typically caused by missing dependencies in the .uplugin file. Checking your UnrealVersionSelector log and adding the required dependencies is the best way to fix this issue.
By keeping your plugin’s dependencies properly configured, you can prevent module loading errors and ensure smooth plugin development in UE5.
