Hey my advice would be to completely unistall combat arms, run unisatller, delete nexon folder on main drive, also deleting pando media files as well.
Then run REGEDIT, HK Current User>software>Nexon and Pando Networks (delete these files)
Also in REGEDIT go to HK Local User>software>Nexon>Pando (delete these files)
and just reinstall CA
for what ever reason my guess is you may have a corrupted secotor in your file. It happens.
any questions feel free to ask, im new to the forum but enjoy helping others. Please give thanks if this helpls