When trying to start ArmA you receive an error Unable to open dynamic link library OPENAL32.DLL
When trying to start ArmA you receive an error Unable to install OpenAL / Returned value was: SomeNumber
When trying to start ArmA the game crashes.
When trying to start ArmA the game shows a message "Bad version of OpenAL32.DLL" or "Missing OpenAL32.DLL".
Download latest OpenAL installer from the OpenAL Website or from Creative Labs OpenAL download or from Webarchive OpenaAL snapshot, install it and reboot. If this does not help, backup files OpenAL32.dll and Wrap_OAL.dll from your Windows\System32 folder (you may want to put them back in case of some trouble), delete them both and run the OALInst.exe again.