Thanks for the reply but the problem was not solved yet and I would like to ask whether there is a tool to make a diagonotic for the VI and find where is the problem because because for the moment the thick row is not broken and I can run the VI but if I want to change something it is a big mess.
There is not much we can do if you cannot post the VI.
You can try VI Analyzer on the VI and see what results you get. Depending on your license, VI Analyzer is part of your installation (in the tools menu) or you have to acquire a separate license for it.
Yes, I tried that tool and I corrected the errors I found but there is no improvement. Is it possible to send the VI to an engineer from NI to treat it in a confidential way?
Depending on the NI branch, it could be possible. But you have to note that a "code review" would be service liable to costs.
Does that require an NDA? If not, you can directly approach NI support with your VI and ask why "Diagram Cleanup" does not work as you expect. This is not liable to cost, but only possible if no NDA is required.....
Sorry for the question but what does it mean NDA and who should I ask precisely knowing I am in Glasgow Scotland.
NDA is the abbrevation for "non disclosure agreement". NI usually does not agree on NDAs if not for paid services.
So if you trust your local NI support team (UK would be yours), you have to go for a paid service, otherwise, you can try the "normal support"....