Why Do I Get Error -1073807300 When Opening a VISA Session?

Updated Jun 8, 2023

Reported In


  • LabVIEW Base
  • LabWindows/CVI Base




  • PIPX40 VISA driver

Issue Details

When using NI-VISA to communicate with a VISA resource, I get error -1073807300 at VISA Open.  

VISA:  (Hex 0xBFFF003C) Insufficient system resources to perform necessary memory allocation.


This error usually occurs when many VISA sessions are open for the same VISA resource. To prevent this from occurring, be sure to close the VISA session when you have finished communicating using the VISA Close VI (LabVIEW) or the viClose() function.

The code below shows how to wire into VISA Close.vi to close sessions. Put this at the end of your LabVIEW code:

Additional Information

You are able to see all the open VISA sessions in LabVIEW following the instructions detailed in How to Acquire a List of Open VISA Sessions in LabVIEW . The image below demonstrates how failing to close VISA Sessions can result in many open sessions using the same VISA resource:

However, if you are using third-party drivers in your application that work with handles generated in LabVIEW these will not show up when using this tool and will remain undetected so ensure you are closing of all sessions created by third-party drivers.

This error code can also occur if there is a problem with one of your driver installations. For more information on how to troubleshoot installation problems, see Troubleshooting Hardware Installation Problems . For example, if it is a GPIB device, make sure the NI-488.2 driver is installed and working. The same is true for VXI devices and the NI-VXI driver.

Users may try to replace another same model hardware or PC.