Report Sub VI called from event structure will not execute in LabVIEW General Posted April 29, 2019 You need to disable the 'Lock Panel (Defer Processing of UI) until event completes' option for the event case. What's happening is that the event structure is locking the UI thread until all code inside of the case completes. In your case you've got another UI coming up which you need to interact with for the case structure to complete. A bit of a catch 22. It might feel wrong that it's happening to you, but there are a variety of good cases that that feature exists and behaves as it does. More commonly, for what you're trying to accomplish, people will make action loops which might receive a message to start open another panel instead of calling immediately from within the structure. However that's a more complicated solution and if you're just trying to keep things simple, then just unclick that option and you'll be off to the races.