I was having this problem myself and finally tracked down the solution. If you look in the event viewer you will notice that these crashes coincide with a critical system event that is linked to Arma3 and "KERNELBASE.dll". The KERNELLBASE.dll issue has already been resolved and is caused by the parameter "largepagefile" being set to 1 in the registry for arma3.exe. Here are instructions for the fix I cannibalized from another thread, hope this helps.

*Click your Start button (assuming you are running Windows 7)
*Type regedit
*Navigate to: [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\arma3.exe]
*Check the value of the "largepagefile"
*It should be "0". If you see a "1", click the "largepagefile" and change the value to "0"
*F5 to save
Exit regedit
Attemt to load Arma as you normally would

I was having this problem myself and finally tracked down the solution. If you look in the event viewer you will notice that these crashes coincide with a critical system event that is linked to Arma3 and "KERNELBASE.dll". The KERNELLBASE.dll issue has already been resolved and is caused by the parameter "largepagefile" being set to 1 in the registry for arma3.exe. Here are instructions for the fix I cannibalized from another thread, hope this helps.

*Click your Start button (assuming you are running Windows 7)
*Type regedit
*Navigate to: [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\arma3.exe]
*Check the value of the "largepagefile"
*It should be "0". If you see a "1", click the "largepagefile" and change the value to "0"
*F5 to save
Exit regedit
Attemt to load Arma as you normally would