Invoke Node Error

[N.Ghrayeb]

Good Morning, 

I created a project with multiple VIs, my main Idea is running the whole project respectively through Next Button. 

my project contain from the first Logo page >> Login Details >> Info Details >> Real Time Data Details and >> Adding new user. 

through the Next Button, it work properly. I created a case structure and inside the true case ( i opened a VI reference using vi path, connecting to an Invoke node (FP-open) >> Invoke node (Run VI) then I close the VI reference and connected it to the error handling. in the False case i created something related to the case itself. 

after that I created a Previous Button (Error Started here ) in the button i build same case structure i used to the Next Button but in previous order. 

when I'm running my VI and move forward from Logo to other VIs it work properly, but when I start going backwards through Previous Button- I'm having an error called (ERROR 1000) - Not in a State Compatible with this Operation.

I read through the instruction, but I guess I'm having a blind spot that I can't figure it out yet. 

Also how can i create a global variable to stop button, now if you pressed the stop button it will shut down the logo vi, i want to make it close the whole project. 

so if you can suggest a solution to me will be great. 

Cheers,

[Bob_Schor]

Sigh.  Attaching your code (in your case, I'd recommend compressing the Folder containing the Project and attaching the resulting .ZIP file) will enable us to better understand what you are doing, as well as get an idea of your level of LabVIEW Experience, the LabVIEW version you are using, and other helpful details.

Some questions that occur to me:

• Do the various VI "Tasks" run to completion before the "Next" button is pressed?
• Alternatively, can the user press "Next" while, say, the Logo task is running and that terminates the task?
• Why are you running your tasks using VI References and Invoke nodes?  Why not simply call the sub-VIs directly as "entire States" of a Simple State Machine?
• Are you familiar with Event Loops to handle Front Panel controls such as the "Next", "Previous", and "Stop" buttons?  Are you familiar with using Shift Registers to hold information (such as "Which State is Next" and "Which State is Previous") for State Machines?
• Do you know about State Machines?
• For your final "Stop" question, I can envision two places for a Stop button -- on the Front Panel of your Main VI (along with Next and Previous) and within one of your sub-VIs (meaning "Stop this one, and when you return to the Main, either stop it as well, or wait for the User to put Main's Stop").  Note that I don't know which sub-VI Stop you intend, so mentioned them both.  This is quite simple to accomplish using the Simple State Machine model -- rather than "doing it for you", you'll get a lot more benefit and enjoyment out of figuring it out for yourself.  As a suggestion, start with the single Stop in the Main, then when you have that working, think about Stop buttons in your sub-VIs.

Bob Schor