This error indicates there is missing or corrupted files in your Combat Arms installation folder. There are a few reasons why this can happen.
Reason 1: Your Anti-Virus is deleting the files
Solution: Temporarily remove/disable your Anti-Virus program.
Explanation: Sometimes some anti-virus programs delete files within Combat Arms. In some cases you can just add Combat Arms to a safe or “White list” which should prevent this from happening. However, if you do not have the means to do this first try disabling your AVS (Anti-Virus Software) and then try running the game. If you still get the error you will need to uninstall Combat Arms and Install it again.
We would recommend using the Nexon Launcher when you download again.
Now launch Combat Arms with your AVS still disabled and see if you still get the error. If you do not then you may need to use a different AVS or find a way to add Combat Arms to its safe list.
Reason 2: You created a new account and it matches the login name of your Combat Arms account.
Solution: Make sure your new account name is different than your Combat Arms account name.
Reason 3: Another program besides an AVS are deleting your game files.
Solution: Use the Msconfig Troubleshooting method to identify the program causing the issue.
Explanation: Sometimes other programs including System Security programs may be causing an issue with your game and deleting game files. By using the Msconfig Troubleshooting method you can find out what program is causing the issue and disable or delete it.