If you are polling too fast (e.g., every 10ms), the slave’s buffer might overflow. Increase the Scan Rate to 500ms or 1000ms to allow the hardware to "breathe." 3. Match Serial Parameters Exactly
Ensure the following settings match exactly between Modbus Poll (Connection > Connect) and your slave device:
Poll a different register address or a different slave ID. If bytes are missing only for a specific register, the issue may be a slave firmware bug.
First, ensure the operating system recognizes your serial adapter.
Zero "Bytes Missing" errors in 48 hours of continuous polling.