Custom Enum for MessageBox

[Dr Cake]

Hello, recently I've been trying to "play" with MessageBoxes and wondered how may I add custom buttons. A basic MessageBox should look like this:

MessageBox.Show("Message", "Title", MessageBoxButtons.Something);

However, I'd like to know how to create one with Once, Weekly, Monthly, Daily and Cancel, instead of MessageBoxButtons.Something. I've tried creating an enum and it displayed on the MessageBox, however, it does let me choose only one of options (Once, Daily, Monthly, etc). How may I make it work properly with MessageBox.Show, so user choose one of these options?

This is how the enum looks like by the way:

public enum Frequency { Once, Weekly, Monthly, Daily, Cancel }