ERROR_CANT_RESOLVE_FILENAME - 1921 (0x781)
The name of the file cannot be resolved by the system.
Updated: Feb 21, 2026
Technical Meaning
The ERROR_CANT_RESOLVE_FILENAME error indicates that the system is unable to resolve a specified file name. This can occur when attempting to access or manipulate a file using an invalid or non-existent path.
Error Details
This error typically arises in scenarios where the operating system encounters issues with file paths, such as incorrect directory names, missing files, or invalid characters within the filename. The error is returned by various Windows API functions that deal with file operations and can be indicative of a wide range of underlying problems.
Usage Context
The ERROR_CANT_RESOLVE_FILENAME error can occur in several contexts where file paths are involved. Common scenarios include:
- Opening or creating files using the CreateFile function.
- Reading or writing to files with ReadFile or WriteFile functions.
- Enumerating files within a directory using FindFirstFile or FindNextFile functions.
Developer Interpretation
When encountering this error, developers should consider several aspects of their code and environment:
- Verify the correctness of file paths used in API calls. Ensure that all directories and filenames are spelled correctly and exist on the system.
- Check for any temporary issues such as network connectivity problems if files are being accessed over a network.
- Validate the security context under which the operation is performed, ensuring that the necessary permissions are granted to access the file or directory.
Related Errors
ERROR_FILE_NOT_FOUND(2)ERROR_PATH_NOT_FOUND(3)ERROR_INVALID_NAME(123)
FAQ
Q: What does the ERROR_CANT_RESOLVE_FILENAME error mean?
A: It indicates that the system cannot resolve a specified file name, often due to an invalid or non-existent path.
Q: How can I prevent this error from occurring?
A: Ensure that all file paths used in your code are correct and valid. Verify the existence of files and directories before attempting to access them.
Summary
The ERROR_CANT_RESOLVE_FILENAME error is a generic indication that the system cannot resolve a specified file name, which can arise from various issues such as incorrect paths or missing files. Developers should carefully validate their file paths and ensure they meet all necessary conditions for successful file operations.