HiAfter start up the captains screen is black the fo is on but if you double click on the screen they come on working enlargedthanks in advanceDave

Do you mean the pfd/nd or the cdu?If its the cdu your fix is here....http://forum.avsim.net/topic/363341-pilots-side-fmc-freezing-up-when-loading-clddrk/page__pid__2267733#entry2267733If its the pfd/nd I've never heard of having this issue with them but it can probably be fixed the same way.