You need to use a valid KSSN. Read in the guide section on how to create an account

"First though, you'll need a KSSN (Korean Social Security Number) and the name that accompanies it."

http://www.dbocom.com/forum/showthread.php?t=59

keep looking

google.com

dbo.netmarble.net. You will need a valid netmarble account. To get one, you'll need a KSSN and a Korean cell phone number to get the sms code to validate your account. Look in the guide section for help on creating an account

Word of advice : there's a section called IMPORTANT TOPICS when coming on the first page of DBOCOM.

Click on EVERYTHING YOU NEED TO KNOW.

Then in the first post made by Citrinate, there's a small quote called Download links. Click on it, it shall reveal a link to a torrent. Download it, get a torrent browser, and the rest will do it itself.