A hijack this report would help in this instance.
please tell me your system specs , EG Operating System , video card , anti-virus , anti-malware , firewall , etc
will also need to know what is in your add-on's if using firefox.
you can first try this
remove gamegaurd folder from your files close browser , use ccleaner and the registry cleaner in that as well do a back up when asked.
restart go to webzen click start game and play. If that dont work will need everything stated above to help you.
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ok either this person had a messed up computer and the ccleaner reg editor messed it up when removing infected reg entries or he got it working and has not posted back.