ERROR_MORE_WRITES - 1120 (0x460)
A serial I/O operation was completed by another write to the serial port. The IOCTL_SERIAL_XOFF_COUNTER reached zero.)
Updated: Feb 21, 2026
Technical Meaning
The ERROR_MORE_WRITES error code indicates that a serial I/O operation was completed by another write to the serial port. Specifically, this occurs when the IOCTL_SERIAL_XOFF_COUNTER reached zero during a serial I/O operation.
Error Details
This error is typically encountered in scenarios involving serial communication where multiple writes are performed on a single serial port. The IOCTL_SERIAL_XOFF_COUNTER is used to manage flow control for the serial port, and when it reaches zero, it signifies that more data can be written without causing a buffer overflow.
Usage Context
This error code is relevant in applications that perform multiple write operations on a serial port. It indicates that the serial I/O operation was completed by another write to the same port, which may affect the timing and sequencing of the writes.
Developer Interpretation
Developers should be aware that this error does not indicate an immediate failure but rather a state change in the serial communication process. The application should continue processing without interruption unless further action is required based on the context of the operation.
Related Errors
ERROR_NO_DATA(232, 0x90): Indicates no data available for read operations.ERROR_BROKEN_PIPE(109, 0x6D): Occurs when a pipe is broken or closed during a write operation.
FAQ
Q: What does the ERROR_MORE_WRITES error code mean?
A: It indicates that a serial I/O operation was completed by another write to the same port. This is typically due to the IOCTL_SERIAL_XOFF_COUNTER reaching zero, allowing more data to be written.
Q: How should developers handle this error?
A: Developers do not need to take any specific action for this error as it does not indicate a failure. The application can continue processing without interruption unless further context-specific actions are required.
Summary
The ERROR_MORE_WRITES error code is a technical indicator used in serial I/O operations, specifically when the IOCTL_SERIAL_XOFF_COUNTER reaches zero. It signifies that more data can be written to the serial port and does not indicate an immediate failure. Developers should understand its context within their application's serial communication logic.