HackShield blocked me!
 
If HackShield blocked you and you're sure you've done nothing wrong, it may just be an issue of Administrator Rights on your computer. If you're not the Admin on your machine, try running the program as an Administrator or even switching to the Administrator account to play. It may solve your problem with being unable to access RO2. 

Another problem you may have with HackShield is that it may not be initializing correctly due to your anti-virus program. Be sure to add HackShield to your anti-virus program's exception list and try opening the client again. If this does not solve your problem, please gather your DXDIAG as well as your Ahn Report information and submit a ticket with the information! BitDefender, in particular, has been giving people errors. Please make sure to add RO2 and HackShield as exceptions!

Gathering Your DXDIAG Information

1. Click the Windows Button and type in dxdiag and hit enter to bring up the DirectX Diagnostic Tool. In older versions of Windows, you may have to go Run... and enter dxdiag when prompted. This will bring up all the information about your machine.
2. Click Save All Information... and save the information to a .txt file. 
3. Navigate to the Submit a Ticket form, choose Technical Support, fill out the forms and attach your dxdiag text file!