We have started to see some users report "Fatal Error!" or something to that effect as of late. Below you will find a few fixes for this issue that have reported as success.
1. Verify your game cache (we know, this sounds obvious and like it will do nothing but one of our users had a corrupt audio file that caused the Fatal Error)
To do this simply right click the game in your Steam Library and click "Properties"
Then click the "Local Files" tab at the top.
You will see a button to verify the game cache as seen below:
2. If the above option doesn't work, you might have an issue with your DirectX install, to repair / reinstall it browse to the Squad Local Install (See the "Browse Local Files" button in the picture above) and navigate into the "_CommonRedist\DirectX\Jun2010" folder, then run the DXSETUP.exe as an administrator. Follow the prompts and you should be able to repair it and hopefully resolve those pesky crashes.
3. A new fatal error has been caused by an outdated Nvidia .dll most commonly found on mobile chipsets (Laptops) The fix for this is to completely remove your driver in safe mode. We recommend using a driver cleaner such as http://www.guru3d.com/files-get/display-driver-uninstaller-download,20.html
To use this software, reboot your PC in safe mode and use the software to uninstall your driver.
If you are not sure how to boot into safe mode: http://www.howtogeek.com/howto/windows-vista/force-windows-to-boot-into-safe-mode-without-using-the-f8-key/
Once you are finished, disable safe mode and reboot again then download your latest driver from the Nvidia website.
This article may change over time if we find more issues causing the same error, stay tuned for further updates on this error.