I try to start up the game; the screen turns black for a while and then I hear the nexon noise or something. The screens flickers on and off and then returns to my desktop, and says "the connection to the server has ended, please try again later."

My computer meets all the requirements, and maplestory has worked before.

Can anyone help me?

just try again. usually i get that message and it works.

Or maybe you started a so-called hack before and now you're comp is infected and so maple refuses to start?

That happens to me sometime..Well sort of what you said..Just open MS again but if it takes a lot of CPU after you exit MS restart and open MS.