Unknown Symbol Compile Error at FP_Open in LabWindows™/CVI™

Updated Jul 12, 2018

Reported In


  • LabWindows/CVI


  • NI-FieldPoint

Issue Details

When I try to compile my FieldPoint LabWindows/CVI project, I receive the error "Undefined symbol" in my compiler log. How can I troubleshoot this issue?


Here are a few troubleshooting steps:

1. Make sure that the Debug mode in LabWindows/CVI is set correctly. In Build » Configuration, verify that you're in Debug mode and not Debug64.
2. Try manually adding the FieldPoint.fp file to the project. To do this, right-click Libraries » Add, then navigate to the FieldPoint.fp file. This can help if multiple versions of LabWindows/CVI were installed on the same PC at the time of the original FieldPoint installation, as the driver install only applies FieldPoint support to the most recent version of LabWindows/CVI on that machine. 
3. Try upgrading to a newer version of LabWindows/CVI and linking the FieldPoint.fp library directly to shared/cvi/bin.
4. Uninstall and reinstall the FieldPoint driver.
5. Completely uninstall LabWindows/CVI and FieldPoint, and then reinstall LabWindows/CVI, followed by FieldPoint.

Additional Information

Note : NI recommends CompactRIO for new designs. Please contact National Instruments if you have questions about the lifecycle of the FieldPoint products.


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