ERROR_DIR_NOT_ROOT - 144 (0x90)
The directory is not a subdirectory of the root directory.
Updated: Feb 21, 2026
Technical Meaning
The error code ERROR_DIR_NOT_ROOT (144, 0x90) indicates that a directory operation was attempted on a path that is not a subdirectory of the root directory. This typically occurs when an application or system function expects a relative path to be within the context of the root directory but receives a path that does not meet this requirement.
Error Details
This error code is specific to file and directory operations in the Windows operating system. It is returned by functions such as CreateFile, CreateDirectory, and others when they encounter paths that are not correctly structured relative to the expected root directory context.
Usage Context
The ERROR_DIR_NOT_ROOT error can arise in various scenarios, particularly when dealing with file or directory operations that require a specific path structure. For example, if an application attempts to create a directory using a path that does not start from the root directory, this error will be returned.
Developer Interpretation
When encountering ERROR_DIR_NOT_ROOT, developers should ensure that paths passed to file and directory functions are correctly structured relative to the expected root directory. This includes verifying that paths are properly formatted as relative or absolute paths depending on the context of the operation.
Related Errors
FAQ
Q: What does ERROR_DIR_NOT_ROOT mean?
A: It indicates that a directory operation was attempted on a path not within the root directory context.
Q: How can I resolve this error?
A: Ensure paths are correctly formatted and relative to the expected root directory when performing file or directory operations.
Summary
The ERROR_DIR_NOT_ROOT (144, 0x90) is a specific error code related to file system operations in Windows. It indicates that an operation was attempted on a path not within the correct root directory context. Developers should ensure paths are correctly structured and validated before performing such operations.