Messagebox Should appear after the Main Form (page)is loaded[appear], How?

(C#): Actually, i have application with in that application, i wrote a "welcome message with Time" in the FormLoad event [application], That'swhy , When i run the application, first loading the messagebox, by clicking ok btn only the main form is loading.

Plz tell me the process, How to write steps to load mainform first in that messagebox should appear?