ERROR_IO_REISSUE_AS_CACHED - 3950 (0xF6E)
Reissue the given operation as a cached IO operation. Requirements Expand table Requirement Value Minimum supported client Windows XP [desktop apps only] Minimum supported server Windows Server 2003 [desktop apps only] Header WinError.h See also System Error Codes Last updated on 07/14/2025
Updated: Feb 21, 2026
Technical Meaning
The ERROR_IO_REISSUE_AS_CACHED error code indicates that a given input/output (I/O) operation should be reissued as a cached I/O operation. This typically occurs when the system determines that caching can improve performance for this particular I/O request.
Error Details
This error is not an actual failure but rather a suggestion to the application or driver to retry the operation with caching enabled. It is part of the Windows API behavior and is intended to optimize I/O operations by leveraging cached data when available.
Usage Context
The ERROR_IO_REISSUE_AS_CACHED error code can be encountered in various scenarios where the system decides that reissuing an I/O request as a cached operation would yield better performance. This might happen, for example, during file or directory operations where previously accessed data is still in cache.
Developer Interpretation
When this error code is returned, it signifies that the application should attempt to reissue the same I/O operation with caching enabled. The developer should handle this by checking if the operation can be retried with a different flag indicating cached I/O, such as FILE_FLAG_WRITE_THROUGH or FILE_FLAG_NO_BUFFERING, depending on the specific context.
Related Errors
- ERROR_FILE_NOT_FOUND (3): Indicates that the file or directory being accessed does not exist. This is unrelated to caching but may occur in scenarios where cached data is expected.
- ERROR_INVALID_PARAMETER (87): Suggests that one of the parameters passed to the I/O operation was invalid, which might affect whether caching can be applied successfully.
FAQ
Q: What does ERROR_IO_REISSUE_AS_CACHED mean?
A: It indicates that an I/O operation should be reissued as a cached operation for potential performance improvement.
Q: How should developers handle this error code?
A: Developers should check if the operation can be retried with caching enabled and attempt to do so.
Summary
The ERROR_IO_REISSUE_AS_CACHED error code is used by the Windows API to suggest that an I/O operation be reissued as a cached operation. This is intended to optimize performance by leveraging cached data when available. Developers should handle this by checking if caching can be applied and retrying the operation accordingly.