Fixing VISA Overrun Error (Error -1073807252 (Hex 0xBFFF006C))

Updated Apr 18, 2023

Reported In


  • LabVIEW


  • NI-Serial

Issue Details

I am using serial communication with VISA to send and receive data from hardware in LabVIEW.  I keep getting the following error:

VISA: (Hex 0xBFFF006C) An overrun error occurred during transfer. A character was not read from the hardware before the next character arrived.


This error occurs when data is available for a subsequent read before the current read has finished executing.  To fix this, we need to read data from the device faster by doing one or more of the following.
  • Increase the baud rate between the computer and the external device
  • Reduce the amount of data being passed through the bus
  • Change the read and write architecture of the LabVIEW VI to Producer/Consumer Architecture
  • Use the VISA Flush I/O Buffer VI by setting the correct buffer type from the VI's options.

Additional Information

If this error is intermittent, you should double-check that your other Instrument Control Properties (such as Parity and Stop Bits) are set correctly for your device.