generate gerber file form cst mws

hello
i have designed an antenna in cst mws and now i want to fabricate them,im wondering how to convert them to gerber file..
any guidance in this regard would be welcome.

use 2D export

From your navigation tree under components, Select you antenna layer(s) then go to File -> Export -> Gerber (Single Layer).

I've tried as you mentioned but it is not working..when I send the file to the fabrication guy,he said that the file cannot be read and it's corrupted..