Take a read here
https://www.digitalcombatsimulator.com/en/support/faq/709/
there are 2 .bat files you can download from the above link, just place them in your main DCS world folder and execut them, first the clean and then the repair.
1) CLEAN https://drive.google.com/open?id=0B1FNNwU4xwU-VU5iX1BWSW41M28
2) REPAIR : https://drive.google.com/open?id=0B1FNNwU4xwU-VU5iX1BWSW41M28
DCS repair is also already in your starprogram file, just cick on windoes start button and type DCS, you have DCS WORLD repair as well.
:thumbup: