ERROR_LOST_WRITEBEHIND_DATA_LOCAL_DISK_ERROR - 790 (0x316)
{Delayed Write Failed} Windows was unable to save all the data for the file %hs; the data has been lost. This error may be caused if the device has been removed or the media is write-protected.
Updated: Feb 21, 2026
Technical Meaning
This error code indicates that a delayed write operation failed, resulting in the loss of data for a specific file. Delayed writes are used to improve performance by deferring the writing of data to disk until a more convenient time.
Error Details
The error message {Delayed Write Failed} Windows was unable to save all the data for the file %hs; the data has been lost. is displayed when this condition occurs. The %hs placeholder in the message represents the name of the affected file.
Usage Context
This error typically arises in scenarios where a delayed write operation fails, such as during system shutdown or power loss. It can also occur if the device hosting the file has been removed or is write-protected.
Developer Interpretation
Developers should interpret this error code to indicate that data intended for a specific file was not successfully written to disk due to a failure in delayed write operations. This may necessitate additional steps to ensure data integrity, such as retrying the operation or manually saving the data.
Related Errors
- ERROR_FILE_SYSTEM_CORRUPTION (259)
- ERROR_WRITE_FAULT (1367)
- ERROR_DISK_FULL (1408)
FAQ
Q: What does this error mean?
A: This error indicates that data intended for a specific file was not successfully written to disk due to a failure in delayed write operations.
Q: How can I prevent this error from occurring?
A: Ensure that the system is properly shut down and that there are no unexpected power losses. Additionally, avoid removing or write-protecting devices while data writes are pending.
Summary
The ERROR_LOST_WRITEBEHIND_DATA_LOCAL_DISK_ERROR (790) error code signifies a failure in delayed write operations, resulting in the loss of data for a specific file. Developers should handle this error by ensuring proper system shutdown procedures and verifying that all necessary writes are completed before dismounting or powering down devices.