ERROR_MUI_FILE_NOT_LOADED - 15105 (0x3B01)
The resource loader cache doesn't have loaded MUI entry.
Updated: Feb 21, 2026
Technical Meaning
The error code ERROR_MUI_FILE_NOT_LOADED indicates that the resource loader cache is missing a Multilingual User Interface (MUI) entry. This typically occurs when an application or system component attempts to access localized resources but cannot find them in the expected location.
Error Details
This error suggests that the necessary MUI files are not present in the resource loader's cache, which can lead to issues with language-specific content and user interface elements. The resource loader is responsible for managing and providing these localized resources based on the system locale settings or explicit requests from applications.
Usage Context
The ERROR_MUI_FILE_NOT_LOADED error may be encountered in various scenarios where an application requires localized resources, such as language packs or regional settings. It can also appear during system initialization or when attempting to load specific user interface elements that are part of a multilingual installation.
Developer Interpretation
Developers should interpret this error code as indicating a failure to locate the required MUI files in the resource loader cache. This could be due to several reasons, including missing files, incorrect file paths, or issues with the resource loader itself. The presence of this error may necessitate checking the installation and configuration of language packs or ensuring that all necessary resources are correctly installed.
Related Errors
ERROR_RESOURCE_DATA_NOT_FOUND(0x20001): Indicates a failure to find required resources, which could be related to MUI files not being loaded.ERROR_FILE_NOT_FOUND(0x3B): A more generic error indicating that the specified file cannot be found, which might also apply in this context if the MUI files are missing.
FAQ
Q: What does ERROR_MUI_FILE_NOT_LOADED mean?
A: It indicates that the resource loader cache is missing a required MUI entry, preventing localized resources from being loaded correctly.
Q: How can I resolve this error?
A: Ensure all necessary language packs and regional settings are properly installed and configured. Check the file paths and verify that the resource loader has access to the correct locations.
Summary
The ERROR_MUI_FILE_NOT_LOADED error code is a generic indication of a failure in locating required MUI files within the resource loader cache. Developers should focus on ensuring proper installation and configuration of language packs and regional settings to avoid this issue.