There are a few steps you can run through before you contact support.
1) Ensure you meet the minimum specifications for the game. They can be found here. If you do not have a dedicated graphics card and you are unable to launch the game, it will almost certainly be the reason as you won't meet the minimum specifications for the game.
Please also check your graphics control panel, if there is a multi-display setting, try setting it to single display and see if that works. Some users have reported that fixes their crashing issues.
If you have an on-board graphics card, make sure that it is not trying to run the game over your dedicated graphics card. You can do this through Steam or through your Graphics card control panel.
3) Try running the game in windowed mode - You do so by right clicking the game in your library, opening the properties, then click on 'Set start perimeter' and type in "/windowed" there.
4) Keep Steam online, but disable the Steam cloud sync. via Properties -> Updates. If you do this, making a physical copy of your save file after each game is recommended.
5) Verify the integrity of the game cache:
a) Via Steam open your game library. Games/View Game Library
b) Open the games properties. Right click game title the Hunter Call of the Wild. Bottom of the menu click on Properties.
c) Select the LOCAL FILES tab and click on VERIFY INTEGRITY OF GAME CACHE...
d) Exit Steam, Reboot your machine and try launching a game session.
6) Microsoft Visual C++
a) Uninstall Microsoft visual c++ 2015
b) Reboot your PC
c) Reinstall it from Microsoft's website.
d) The try to launch the game again.
7) Errors with api-ms-win-crt-runtime-l1-1-0.dll - This error is mostly connected to the version of WinSDK.
The correct version for theHunter: Call of the Wild is WinSDK-10.0.10586.0.0 which can be downloaded from Microsoft's website.
8) Try setting your Screen Space Reflections to 'On'.
You can do this in the graphics settings in the main menu, in game menu or through the following method out of game:
C:\Users\USER\Documents\Avalanche Studios\theHunter Call of the Wild\Saves\settings\STEAMUSERID>settings.json then set "GraphicsSSReflection": 0 to 1
9) Uninstall and then download a fresh copy through steam.
10) Some users have reported the following working:
a) Turn off Steam overlay
b) Disable background programs for recording and screen capturing
c) Temporarily disable your antivirus software
11) If the above did not help, send us your dxdiag file and let us know that you have completed all of the above. Details on how to get your dxdiag file can be found here.