I had yesterday a problem after installing 1.55 patch. After patching OA it worked 1-2 times, but after that when I try to launch OA, mouse pointer shows 'working background' about second and nothing happens. I reinstalled ArmA2+OA. It worked again one or two times.
These things might narrow the problem little:
-There isn't anykind of error messages and arma2oa.rpt doesn't change.
-When watching windows task manager arma2oa.exe runs about 1 second. Same happends if I try to launch BAF.
-ArmA2.exe works fine.
-Restarting computer doesn't work
-Running in compatibility mode doesn't work.
-Removing config files from My Documents doesn't work.
-Rerunning 1.55 patchfile doesn't work.
-I got latest catalyst drivers.
system:
AMD PhenomII 965, 6GB RAM, ATI HD5770, win7 x64
Arma2oa.rpt