thanks reply william.
I use the answer of sergey. i slove my problem. I set a font in my scx. this font is not english. it was arabic. I thing unicode langueages and some not english have this problem. If font is not include in windows font foldes. Intstalle spreately. scx check the name of font windows font folder and check the fontchr. English font have abality to change with other font. But fontchar not have.

May be i am not true all but when i brows the scx and changes the font name my problem sloved.
thanks for you reply