Hello,
Thank you for reporting the issue.
We need crash dump files from this folder for solve your problem.
C:\Users\<Name>\AppData\Local\Arma 3\
Can you upload somewhere in winrar package please?
When the archive is smaller than 5000k, you can attach it here. When it is bigger, please use some free sharing service and post link here.

How to find correct crashdump file:
Try to make the crash happen
Look into crashdump folder
Upload crashdump with latest date in name (crashdump is rpt + bidmp + mdmp file with same name). Please try to provide as many crashdumps as possible, it helps us investigating the problem in a big way.

Thank you.

http://feedback.arma3.com/how-to-user.html

No such folder exists. Only (relevant) folders are BohemiaInteractive and Arma 3 Launcher. In Arma 3 Launcher there is a folder "Logs" and inside that there are three .rpt files, but aside from that I do not have what you're looking for.

Have you tried running the game as administrator? It is possible that it does not have the rights to write into your documents folder.

I have tried to no avail.

Could you please upload your DX-Diag file? It would help us a lot.
You can find how to get your file here:
http://www.matrixgames.com/forums/tm.asp?m=1597548

Thank you.

Uploaded.