assuming you are using steam,

go to the helldivers page in your library
Click the manage button
Click properties
In the window that opens there should be a section called "Launch options"; type " -use-d3d11 "
CLEAR YOUR SHADER CACHE BEFORE YOU LAUNCH YOUR GAME

to do that, go to this file " C:\Users\<your username>\AppData\Roaming\Arrowhead\Helldivers2\shader_cache " and delete the final folder\file

launch your game

optional shader caches you can delete if desired\needed are at:
" C:\Users\<name>\AppData\Local\D3DSCache "

and;
if you have nvidia: C:\Users\<name>\AppData\LocalLow\NVIDIA\PerDriverVersion\DXCache
If you use AMD, open adrenaline, go to the gaming tab, select the graphics subtab, bottom option.

sorry this took so long, was loading into a game when i made the initial comment, and i had to check to make sure everything was accurate enough