Overview
Before starting this guide see if you get an x3daudio error when you start the game out of its directory. This guide is for those who couldn’t start the game on a windows 64 bit. This has worked for me in ARMA 2 and ARMA 2 Operation Arrowhead.
The x3daudio.dll error that appears when you start the game from its directory.
Ok so i installed ARMA 2 on my Vista 64 bit home premium and it crashed on startup.
I fully reinstalled (I used steam in administrative mode) and still had a problem (just a microsoft error message).
Out of curiosity i started ARMA 2 out of its’ steam directory and got an error stating x3daudio.dll was missing.
Then I did a reinstall and reboot for DirectX.
The problem was still there so i think “what if i find the file in the .cab file from the directx folder and copy it to the directory” (I only thought about this because I have used d3d9.dll based shaders in other games).
I found the file X3dAudio1_6.dll in the Mar2009_X3DAudio_x86.cab with 7Zip and copied the file to the base Arma 2 directory.
Now the game loads up and I can get in game just fine. (I think 64bit windows tries to only load the 64 bit Directx only and i don’t know why)
(this worked for me on operation arrowhead too)
Note: I used the x86 cab file and not the x64