This is how I typed it into the Minetest CONF
video_driver = direct3d9
Then when I tried to go Single Player and Server it works for a few seconds and goes to this:

Whenever I try to go back in it repeats the message.
Then this happens:

And when I exit:

Now I have read some other problems about this and the answers are not working for me.
If you can give me a detailed explanation then that will be great. Thanks
(P.S When I removed the direct3d9 from the MT Notepad it worked properly.)