What is "make a single instance application" in VB.NET?

Question

Does it mean that the program can only be opened once? Will it mess with the code that I have already written? What does it exactly mean?

Answer 1

It means your application is supposed to have only one instance. My last project wanted a minimized instance to pop up if somebody tried to open another one. Spotify works like that, for example.

It won't mess up your code. You just must enhance your startup code or Form.