Multiple .EXE Sessions

I did create an .exe file of my excel sheet. It appears that I can run multiple sessions of this file on my computer. How is this possible ? As I intend to allow only single user access, this would not seem possible if the exe would be activated on a server and various user could work at once with it. I have also tried copying the file in explorer and starting the renamed file which also did work. Ideally I would like to avoid this possibility too.
Is there any solution to these 2 issues ? Thanks

You can configure XLS Padlock to lock workbooks to one computer only. And no, uploading it to a server won’t allow others to use the locked workbook.
Now regarding multiple sessions, you can try this: