Sorry for replying to such an old thread but I need help. OpenJK SP and MP worked perfectly fine on my old computer. But when I moved the files over to my new one OpenJK SP works but MP simply refuses, it won't even show me a window with an error. I click it and nothing happens. I even redownloaded OpenJK like 4 times to see if it fixed it and it was always the same result. OpenJK SP works fine but OpenJK MP does absolutely nothing. If it means anything I also have MBII installed which works fine, though I have it set to it's own client and not OpenJK, though the window still says openjk so I don't know if that's interfering or anything. I'd post a screenshot, but there's nothing to post. Like I said open jk MP just simply does nothing, no error window no popup, nothing clicking on it has no effect.