When I dump fuel, instead of the fuel being white, its huge black squares coming from the wingtips. This happens to me everytime i use the pmdg 777. Ive also noticed to same problem with the extra 300 smoke on coming from its tail. All black squares, no white fluffy smoke coming. Someone told me that I am missing some texture files. Where can i get these texture files? 

 

These are the type of black squares I am talking about.

Any missing files will be restored by the installer if you run it and select REPAIR.