Frontpanel freezes when an event of an already closed event structure occurs

Hello,
I´d be very glad if someone could explain to me the behaviour of the attached short and simple vi.
If you press the OK button #1 once and then the OK button #2 the vi finishes, but if you press the first button more than once before pressing the second button, the front panel is locked. In both event structures, the feature "Lock front panel until the event case for this event completes" is enabled. If it is disabled the front panel is not locked after pressing the first button twice. What I do not understad is why if the feature is enabled the front panel locks after pressing the first button twice. I would think that after the loop containing the event structure closes, the event case should definitively be completed.
Attachments:
Event.vi ‏12 KB

This is expected behavior.
If you look at your event configuration, both events are set to "lock front panel until event completes". If you fire the second event first, the FP locks and you cannot trigger the first event any more.
Quick and dirty solution: uncheck "lock front panel...".
Better solution: learn about dataflow and proper program design. What you are doing here is not a good program architecture. Deadlocks, too sequential,  event structures that cannot be serviced immediately due to dataflow dependency, etc.
Maybe you can tell us in a more general way what you are trying to do.
LabVIEW Champion . Do more with less code and in less time .

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