Why Do I Get Error 1026 When Saving References in an FGV?

Issue Details

When I save references for dynamic calls in a Functional Global Variable(FGV) I get an error:

Error 1026 occurred at Call By Reference in Reference FGV.vi 
Possible reason(s): 
LabVIEW:  VI Reference is invalid. 

How can I avoid this problem?

Solution

If you save a value in an uninitialized shift register, you can still obtain that value after stopping and later restarting the VI. You can also save a reference for a dynamic VI call inside a FGV shift register. However, if you try to call the VI by that reference after stopping and restarting the VI again, you will get the above error; stating that the reference has become invalid. When stopping a VI, the memory allocated for the dynamic VI call gets released. You can still access the address of that memory when you read the reference but the reference is invalid. To avoid this problem, don't stop the calling VI between getting the reference and using it.