I can't search for this error but since I have a screenshot here. please help me out.

This happened when I finished compiling and when I test it, it just shown a black screen like so. I dont know what it is. I also upload my .map file so you can help me figure it out. Thanks

I get that if I forget to add a skybox or miss a big bit out sometimes.

Ok, just looked at your map, as a dot.map.
you are using custom textures have ?
have you set up a texture folder.
I have not got them textures so all I see is the map in blue and caulk.
the game can't find the texures your using.
also the skybox should turn red when you get it right, just see if it does with a stock sky, mp_carentan

Looked again,
you have 2 caulk boxes around your map, plus you have a skybox.
remove both caulk boxes, you will lose your top sky, just redo the top only. and bring all 4 sides of the skybox up to meet the floor, for a nice square finnish.
If you want arty to work in the map then the top sky should all be textured, all six sides for the arty to get in, if your roof is to low.
Player spawns need to be a little bit of the floor not on it, so they don't get stuck in the map.

Thank you very much, it worked!!
Anyway, I upload the map again with texture.
Please check out if it had any other error.
Thanks

Textures now showing.
Skybox is blue, needs the top on it, look under map at the sides and the floor, they should all with the sky roof make a hollow sealed box to prefend leaks.

way past my bed time, will look again in the morning.