Hi Eki, In response to your question, I do not believe macros will prevent a user from closing an Excel file. Macros are comparable to scripts that help automate a task that you may want to run repeatedly. To workaround your problem, you can have LabVIEW automatically reopen an Excel file if it has been closed outside of LabVIEW. Otherwise, if LabVIEW is generating any errors with the Excel file not open, you have incorporate error handling in your program and subsequently reopen Excel.
Hopefully this will give you some pointers to solving your issue. Good luck! Kileen C. Applications Engineer National Instruments
