Arma 2 combined ops on steam wont start

[Sir frags alot]

Hello.
My arma 2 co has not launched since i verified my Arma 2 cache.There is no error message it just does not start.Ive tried reinstalling arma 2 and OA and verfying the cache but it still wont work.It worked fine before but since i did that it wont launch.OA and arma 2 work just fine.

when i go to launch CO, a black box appears for a half a second.im not sure but i think it is a DOS file.This always happend when i launched co before and CO started up fine unless i closed the steam window.If i did the steam window it it would co wont start much like its doing now.

my operating system is windows 7 64 bit.sorry if i did not explain my problem well
also, i dont know if this may have something to do with the problem,but i keep all my addons in the addons folder for arma 2 ive never had any problems with doing that,since i dont ever use arma to by itself.
i also installed OA first before i installed arma 2

in short,i think verfing my arma 2 game cache may have messed up CO

Upon screen shotting the black box it seems to say this error:ERROR the system was unable to find the specified registry key or value

Thank you

[[R-DEV]Thermis]

First try searching through other threads before posting a new one. We've dealt with similar problems multiple times. The way you use addons while not recommended shouldn't be causing a problem. You might have to reinstall both games, and I suggest you do this first before trying the below fix. Along with removing all your addons so you are starting completely from scratch.

If you are still having issues after trying all of this, post here and be as detailed as possible.

For Steam users that may have issues
Look inside the directory:
Code:
C:\Program Files\Steam\SteamApps\common\arma 2 operation arrowhead
Find the file:
_runA2CO.cmd

[Von_Emmy]

have you updated your win 7 64 bit with Service pack 1 before?

I have the same issue! my CO won't run any more. But i'm not using the steam version!
I also have win 7 64 bit and did have service pack 1 installed today. I'm using the "@folder" addons methodology and Arma 2 and OA are installed in the same folder.

Things i've tried until yet:
- updating windows with all the latest updates
- updated my Nvidia graphics driver with the latest ( 266.58 )
- to start the game in different compatibililty modes also with desktop design disabled
- repatched my Arma 2 ( 1.08 ) and OA ( 1.57 )

My Sys specs are:

Win 7 64 bit (installed on a Intel SSD)
Gigabyte GA -EX58 Extreme
i7 920 @ 3.2 (only 2 cores enabled)
6 GB RAM (3x2GB 1600 MHz)
EVGA GTX 295 Copperhead (Watercooled)
WD Caviar Black 1TB SATA3 on a SATA2 connector (1 for Games and 1 for Media)

need HELP!!!

[ZAP44]

Have the same setup, Win7 64 and Steam and had the same problem. Start over. Start Steam via "run as administrator". Next before you do anything else run ArmA 2 once. This will write keys to the registry or CO will not work. When you have ArmA2 and OA installed and have run ArmA2 once use the "Launch ArmA2 Combine Ops option in Steam. If you have additional problems suggest looking in BIS forums Bohemia Interactive Forums - Powered by vBulletin

[Sir frags alot]

Thank you for the help everyone. ZAPs seemed to solve the problem for me.

[OverwatchX]

Installation guide for Operation Arrowhead, ACE and ACRE

[Psyko]

i've been having this problem for ages. it also effects my CIV 5.

the error report says it needs DX8, i should have DX 11, but Civ 5 only allows me to use DX9. Its most likely to do with steam itself and not OA.

I followed the above instructions and was told to do the same thing yesterday by Steam tech support. I was refered back to steam tech support when i made a support ticket for AO's forum.

So if anyone knows how i can update my dx 11 and get it back to normal please explain in detail. I tried updating manually before but got a download link for a load of rar files with no explination as to what to do with them. and im not even certain if it willl work.

Does anyone know if DX gets updated by windows update, or its only through game installations?

[[R-COM]MaSSive]

Psyko run Dxdiag and see if you get any errors. If not all is fine with your DX11. It gets updated automatically when there is update for it.

If you need to run DX9 game and have problems with it failing to start, try installing latest dx9 redistributable. Before you ask, yes I know you have DX11 just install this and it will be fine.

Download: DirectX Redist (June 2010) - Microsoft Download Center - Download Details