ERROR_EVENTLOG_FILE_CHANGED - 1503 (0x5DF)
The event log file has changed between read operations.
Updated: Feb 21, 2026
Technical Meaning
The ERROR_EVENTLOG_FILE_CHANGED error code, with a numeric value of 1503 and a hexadecimal representation of 0x5DF, is returned when the event log file has been modified between read operations. This indicates that the state of the event log file has changed during an attempt to read it.
Error Details
This error typically occurs in scenarios where multiple processes or threads are attempting to access and read from the same event log file simultaneously. If one process writes to the log while another is reading, the second process may encounter this error because its previous read operation was based on an outdated state of the log.
Usage Context
This error code can be encountered in various applications that interact with Windows Event Logs, such as custom logging utilities or diagnostic tools. It is particularly relevant for applications that require consistent and reliable access to event logs without interruption from concurrent writes.
Developer Interpretation
When this error occurs, it suggests that the application should handle the situation by retrying the read operation after ensuring that any pending writes have completed. This can be achieved through proper synchronization mechanisms or by implementing a retry logic with appropriate delays between attempts.
Related Errors
FAQ
Q: What does the ERROR_EVENTLOG_FILE_CHANGED error mean?
A: It indicates that the event log file has changed between read operations, suggesting a potential race condition.
Q: How should I handle this error in my application?
A: Retry the read operation after ensuring any pending writes have completed or implement proper synchronization mechanisms.
Summary
The ERROR_EVENTLOG_FILE_CHANGED (1503) error is a specific technical indicator that the state of an event log file has changed between read operations. Developers should handle this by implementing retry logic and ensuring proper synchronization to maintain consistency in their applications.